Language：Japanese   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.cattod.2019.12.023

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© 2018 Elsevier B.V. The Ag-loaded perovskite-type oxide catalysts (Ag/LaFeO3-CN and Ag/LaFeO3-imp) were prepared using two different methods, and their catalytic activities for carbon combustion were examined. Ag loading was observed to exhibit a positive effect on the catalytic activity of carbon combustion for an Ag/LaFeO3-CN catalyst that was prepared by the calcination of an Ag-loaded heteronuclear metal cyano-complex precursor. However, Ag loading was not observed to be significantly effective in case of Ag/LaFeO3-imp that was prepared by a general impregnation method. Such a noticeable enhancement in the activity of an Ag/LaFeO3-CN catalyst was assumed to originate from both the high dispersion of Ag that was loaded on LaFeO3 and from the formation of reactive oxygen species between metallic Ag species and the perovskite-type oxide.

DOI： 10.1016/j.cattod.2018.08.019

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Electrochemical Society Inc.  

The growth of Ni grains in sintered 60wt%Ni-BCY anode supports for solid oxide fuel cells and their electrical conductivities were evaluated. The critical grain growth was confirmed in a Ni-BCY disk sintered at a temperature higher than 1450 °C, resulting in a large degree of decline in electrical conductivity. In addition, reducing the Ni content in Ni-BCY did not effectively suppress the Ni grain growth. Addition of GDC into the Ni-BCY (Ni-BCY-GDC) was found to effectively inhibit the Ni grain growth after sintering at 1450 °C, which remarkably enhanced the electrical conductivity compared with those of the Ni-BCY supports. Adding GDC into BCY simultaneously suppressed the grain growth of the BCY. The grain sizes of Ni are in a linear relationship with grain size over volume fraction (r/f) of the oxide phase, implying that the Ni grain growth was prevented by the pinning pressure from the oxide grains.

DOI： 10.1149/09101.1963ecst

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2019f.0_166

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.catcom.2018.08.011

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2109/jcersj2.18033

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier B.V.  

Fe-bipyridine complexes were encapsulated into cation-exchanged Y-type zeolites (M-Na-Y: M = K+, Cs+, Mg2+, Ca2+, NH4 +, TMA+, and TBA+) and their catalytic activities for oxidation of benzene with hydrogen peroxide (H2O2) to phenol were investigated in three types of solvents (CH3CN, H2O, and CH3CN + H2O(1:1)). Regardless of the kind of solvent, the counter cation in [Fe(bpy)3]2+@M-Na-Y did not affect the selectivity to phenol. No significant difference in catalytic activity of [Fe(bpy)3]2+@M-Na-Y appeared in CH3CN + H2O (1:1), while a difference on catalytic activity appeared in each CH3CN and H2O solvent. It was suggested that the catalytic activity is related with the accessibility of benzene to [Fe(bpy)3]2+ site in [Fe(bpy)3]2+@M-Na-Y, controlled by the hydrated ionic radius of the counter cation introduced. The effect of ligand coordinated with Fe ion was investigated by comparing the catalytic activities for oxidation of cyclic hydrocarbons (benzene, cyclohexane, and cyclohexene) over [Fe(bpy)3]2+@Na-Y, [Fe(phen)3]2+@Na-Y, and [Fe(terpy)2]2+@Na-Y (phen = 1,10-phenanthroline and terpy = 2,2′
6′,2″-terpyridine). It was suggested that the expansion of π-electron over the ligands such as phen and terpy improves the uptake ability of substrates having π-electron such as benzene.

DOI： 10.1016/j.cattod.2017.10.047

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Language：English   Publishing type：Research paper (scientific journal)  

© 2018 American Chemical Society. [Cu(terpy)]2+ complexes encapsulated into Na-Y zeolite ([Cu(terpy)]2+@Y) were prepared, and their catalytic activities for the oxidation of sulfides using hydrogen peroxide were investigated. Several spectroscopic results, as well as elemental analysis, demonstrated the formation of [Cu(terpy)]2+ complexes in supercages of Y-zeolite. [Cu(terpy)]2+@Y exhibited high selectivity for the oxidation of thioanisole into methylphenylsulfoxide when H2O2 was used. The kinetic study of this oxidation at the catalyst [Cu(terpy)]2+@Y suggests that the reaction of [Cu(terpy)]2+ species with H2O2 is the rate-determining step. The oxidation of thioanisole, benzene, and 2-phenylethylamine using [[Cu(terpy)]2+@Y]∗, which was prepared from the reaction between [Cu(terpy)]2+@Y and H2O2, quantitatively proceeded to methylphenylsulfoxide, phenol, and 2-amino-1-phenylethanol, respectively. The reaction of [Cu(terpy)]2+@Y and H2O2 was found to yield thermally stable but active CuII-OOH species in [Cu(terpy)]2+@Y.

DOI： 10.1021/acscatal.7b04092

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5004/dwt.2018.22314

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：John Wiley and Sons Ltd  

P(AA)-Ag heterogeneous catalyst system comprised of Ag nanoparticles embedded within hydrogel matrices has been described for the selective aerobic oxidation of alcohols and reduction of nitro phenols in water. P(AA)-Ag nanocomposite was characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), X-Ray photoelectron spectroscopy (XPS) and inductively coupled plasma atomic emission spectrometer (ICP). Catalytic activity of p(AA)-Ag catalyst was investigated in the aerobic oxidation of primary alcohols and reduction of nitro compounds by emphasizing the effect of different parameters such as temperature, catalyst amount, substituent effect, etc. The catalyst was easily recovered from the reaction medium and it could be re-used for other three runs without significant loss of activity.

DOI： 10.1002/aoc.3917

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Electrochemical Society Inc.  

The membranes consisting of samaria-doped cerias, (SmO1.5)0.2(CeO2)0.8 (SDC), containing 10~50 wt% nickel were formed by electrophoretic deposition (EPD). The membranes were examined as SOFC anodes fueled with 6% ammonia. The catalytic activity of ammonia decomposition was higher in the lower Ni contents of 0~30 wt%. The anodic performances were similar between 10~40 wt%. The impedance analysis of the anodes suggested that increase in the Ni content increased the resistance of electrochemical oxidation, and deceased in the low frequency component, which might be assigned to a molecular diffusion process.

DOI： 10.1149/08513.0779ecst

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2018f.0_165

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

This study aimed to investigate a cerium triethanolamine complex precursor for the self-propagating high temperature synthesis (SHS) of highly dispersed ceria-supported noble metal catalysts. The cerium complex precursor (Ce-TEA) was prepared by mixing cerium nitrate and triethanolamine and analyzed its decomposition by the thermogravimetry and differential thermal analysis. It was found that, in air, Ce-TEA undergoes a thermal runaway at approximately 250 degrees C. This result suggested the possibility of inducing a self-sustained decomposition process at room temperature. In addition, the precursor can easily coordinate with metal noble nitrates in an aqueous solution. As a result, preparation of ceria-supported noble metal catalyst can be achieved by local ignition of the resulting noble metal doped cerium precursor. This novel approach can be used to yield Pd/CeO2 catalyst with various Pd loading in a single step without further annealing. XRD and XPS results of the prepared catalyst suggest that palladium is highly dispersed in its ionic state on the ceria support.

DOI： 10.1016/j.ceramint.2017.07.208

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Hydrogen permeation properties of Gd0.1Ce0.9Ox/BaCe0.80Y0.20O3-delta (GDC/BCY) dual-phase membranes were evaluated. Nongalvanic hydrogen permeation was observed for 46 vol% GDC-containing BCY membranes: the permeation rate was 0.30 ml.min(-1).cm(-2) at 800 degrees C. This is almost comparable to the reported value of Ni-BCY cermet (0.50 ml.min(-1).cm(-2)). This nongalvanic hydrogen permeation unambiguously indicates that the BCY-GDC composite functions as a mixed proton-electron conductor in an H-2 reducing atmosphere. From a conductivity analysis, it was deduced that 46 vol% GDC/BCY possesses proton and electron conductivities comparable to the bulk states of BCY and GDC. The composite membrane was stable in an atmosphere switching between H-2 and air. TGA analysis indicated that addition of GDC enhanced the stability of the BCY phase in CO2. (C) 2017 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.16230

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

The effect of oxygen diffusion on the thermal decomposition kinetics of La[Fe(CN)6].5H(2)O has been explored. In particular, the critical conditions under which LaFeO3 can be synthesized via solid-state combustion of this cyano complex precursor were analytically and numerically investigated. Thermal analysis experiments as well as simulations showed that the oxygen diffusion enhancement facilitates the formation of a self-propagating combustion front during the decomposition of La[Fe(CN)(6)].5H(2)O. As a consequence, the sample undergoes local overheating that raises its temperature by several hundreds of degrees. This enables the production of LaFeO3 perovskite-type oxide with a minimum contribution of external heat resources. Although the self propagating high-temperature method has already proven to be successful for the synthesis of perovskite-type oxides from cyano complex precursors under oxygen atmosphere, we will show that under the appropriate settings, air can be used instead. Moreover, the temperature of the front is related to the ease of oxygen diffusion. Therefore, the surface area and the crystal size of LaFeO3 perovskite-type powders obtained via solid state combustion have been controlled by controlling the gas flow rate at which the sample has been exposed during the treatment.

DOI： 10.1016/j.ceramint.2016.11.134

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Anode-supported solid oxide fuel cells with a thin layer of proton conducting BaCe0.8Y0.2O3- (BCY) were fabricated by electrophoretic deposition technique using an organic suspension. BCY green films were formed on a graphite-added NiO-BCY substrate. By the classification of particle size distribution by the suitable period of sedimentation yielded a crack-free green film. Sintering of the crack-free green film at 1450 degrees C yielded a dense layer of BCY with the thickness of about 9.2 +/- 0.3 mu m after sintering at 1450 degrees C. The BCY thin film on the NiO-BCY substrate exhibited conductivity of 1.6 x 10(12)S.cm(-1) at 600 degrees C and its activation energy was 0.35 eV. The anode-supported single cell with the BCY thin film resulted in the maximum power density of 74.2mW.cm(-2) at 600 degrees C. (C) 2017 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.17048

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2017f.0_121

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2017f.0_125

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A Zn-Sn precursor with cubic-shaped particles was successfully prepared by a simple coprecipitation method to obtain Zn-Sn mixed oxide (ZTO) catalysts. The resulting ZTO catalyst maintained the cubic shape even after calcination at 900 degrees C. The catalytic activity for the cyanosilylation of benzaldehyde with trimethylsilyl cyanide increased with increasing calcination temperature, and reached the maximum value at 600 degrees C. The ZTO catalyst calcined at 600 degrees C exhibited higher catalytic activity than the other solid acid catalysts, SiO2-Al2O3 and Amberlyst 15 DRY.

DOI： 10.1246/cl.160320

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Language：English   Publishing type：Part of collection (book)   Publisher：Wiley Blackwell  

The perovskite-type oxide catalyst, LnFeO3 (Ln = La, Pr, Sm, Gd, and Dy), prepared by decomposition method of heteronuclear cyano complex precursor (CN method) was applied to liquid-phase organic reaction, cyanosilylation of benzaldehyde with TMSCN. The catalytic activity per specific surface area over LaFeO3 was dependent on calcination temperature in CN method and it was found that the catalytic activity was strongly related to crystallinity of catalyst. The catalytic activity of LnFeO3 catalyst increased with decreasing ionic radius of A-site lanthanoid ion. The catalytic activity of LnFeO3 catalyst was found to increase with increasing surface oxygen concentration on LnFeO3, which was estimated by XPS results.

DOI： 10.1002/9781119234463.ch8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Perovskite-type oxide, LaFeO3, was prepared from coordination polymer precursor, La[Fe(CN)(6)]center dot 5H(2)O by calcination with the different two systems. In a muffle furnace system, the perovskite-type oxide was given by calcination at >500 degrees C. The specific surface area of LaFeO3 powder calcined at 500 degrees C for 24 h was 18m(2).g(-1), which was the largest among single phase perovskite-type oxides calcined in a muffle furnace. In a gas-flow system, the perovskite-type oxide was given by calcination at significantly low temperature (>250 degrees C). The specific surface area of LaFeO3 powder calcined at 300 degrees C for 1 h in a gas-flow system was dependent on O-2 partial pressure. (C)2016 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.15198

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2016f.0_93

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MYU, SCIENTIFIC PUBLISHING DIVISION  

Temperature-programmed reduction measurement combined with resistance measurement (TPR&R) was performed to investigate the reduction behavior of the samples containing the semiconductor materials, SnO2 and CuO/SnO2. The four reduction peaks were observed in the H-2-TPR profile of SnO2, being assigned to the reductions of surface adsorbed oxygen species, surface lattice oxygen, amorphous SnO2 and bulk SnO2. On the other hand, the H-2-TPR profile of CuO/SnO2 was more complicated than that of SnO2. The TPR&R measurement enabled definite assignments of the six reduction peaks of CuO/SnO2: the reductions of (I) Cu2+ to Cu+ in highly dispersed copper oxide, (II) bulk CuO to Cu, (III) Cu+ to Cu in highly dispersed copper oxide, (IV) SnO2 lattice oxygen interacting with highly dispersed copper oxide, (V) amorphous SnO2, and (VI) bulk SnO2.

DOI： 10.18494/SAM.2016.1281

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2016f.0_90

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

The perovskite-type oxide catalyst, SmFeO3, prepared by decomposition method of heteronuclear cyano complex precursor (CN method) was applied to liquid-phase organic reaction, cyanosilylation of benzaldehyde with TMSCN. The maximum catalytic activity per catalyst weight was achieved at 800 A degrees C of calcination temperature in CN method and it was found that the catalytic activity was strongly related to the crystallinity of SmFeO3 catalyst. The catalytic reaction performed in the presence of pyridine and 2,6-di-tert-butylpyridine suggests that the catalytically active sites are the Bronsted acid sites formed on the SmFeO3 catalyst. The catalytic activity of SmFeO3 catalyst prepared by CN method was much higher than those of acid catalysts: SiO2-Al2O3 and Amberlyst.

DOI： 10.1007/s11164-015-1980-y

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The decomposition of La[Fe(CN)(6)]center dot 5H(2)O and La[Co(CN)(6)]center dot 5H(2)O under different atmospheres has been analyzed by thermogravimetry (TG) and differential thermal analysis (DTA). In addition, the decomposition temperature at different sample locations was monitored for sample masses around 2 g of La [Fe(CN)(6)]center dot 5H(2)O and La[Co(CN)(6)]center dot 5H(2)O, when they were calcined for 1 h at temperatures ranging from 200 to 400 degrees C in a controlled gas-flow system. Results showed that, the large enough of the cyano complex precursors undergo combustion when they are decomposed under oxygen atmosphere. X-ray diffraction results revealed that perovskite-type oxides crystallize due to the overheating of the process. As a result, it has been possible to produce LaFeO3 and LaCoO3 perovskite-type oxide powders by SHS under oxygen atmosphere using La[Fe(CN)(6)]center dot 5H(2)O and La[Co(CN)(6)]center dot 5H(2)O as a precursor. The effect of the ignition temperature has been investigated. The specific surface area of the perovskite-type oxides produced via SHS using heteronuclearcyano metal complex as a precursor is significantly higher than that of other LaMO3 produced using the same technique but obtained from other type of precursors. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2015.07.246

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Catalytic activity of iron complex-encapsulated zeolite catalyst ([Fe(bpy)(3)](2+)@Y) for oxidation of benzene increased with increasing the amount of water added to acetonitrile. Maximum value of catalytic activity was obtained when the volume ratio of the solvents was equal (CH3CN:H2O = 1:1). After reaction at 24 h, the turnover number of [Fe(bpy)(3)](2+)@Y was higher than that of [Fe(bpy)(3)](ClO4)(2) as a homogeneous catalyst.

DOI： 10.1246/cl.150479

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Bilayer Ni-YSZ anode films for SOFCs were prepared by electrophoretic deposition (EPD). The thickness of each layer of the bilayer anode films, which consist of 50 wt% Ni-YSZ as the active layer and 70 wt% Ni-YSZ as the current collecting layer (50Ni-YSZ/70Ni-YSZ), were controlled by the deposition time of the EPD process. For the monolayer anodes, 70Ni-YSZ showed a better performance than 50Ni-YSZ. The bilayer film, 50Ni-YSZ/70Ni-YSZ, showed an even better performance than the 70Ni-YSZ monolayer film. Probably, 50Ni-YSZ anode has more reaction sites compared to 70Ni-YSZ; on the other hand, 70Ni-YSZ has higher porosity to be a gas diffusion (or current collecting) layer. The anodic performance of the bilayer film significantly depended on the film thickness of the 50Ni-YSZ layer, and 3 mu m was found to be the optimized thickness as the active layer, which suggests that the charge transfer reaction site extended up to a 3-mu m thickness from the anode/electrolyte interface. (C) 2015 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.123.235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Fe-bipyridine complexes encapsulated into Na-Y ([Fe(bpy)(3)](2+)@Y) were prepared and their catalytic activities for oxidation of cyclohexene with hydrogen peroxide in CH3CN and H2O solvents were investigated. The prepared [Fe(bpy)(3)](2+)@Y was characterized by several methods and it was found that slightly distorted or compressed [Fe(bpy)(3)](2+) ions were formed within supercages of Y-type zeolite. [Fe(bpy)(3)](2+)@Y catalyst exhibited both higher activity and higher selectivity to 2-cyclohexen-1-ol in water solvent than another Fe catalysts. In addition, the selective hydroxylation of cyclohexene to 2-cyclohexen-1-ol with molecular oxygen was successfully achieved for [Fe(bpy)(3)](2+)@Y catalyst. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2014.07.038

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Language：Japanese   Publisher：The Japan Petroleum Institute  

The adsorption of Hg(II) from aqueous solution by activated carbon obtained from date palm  was studied. In the present study, ZnCl₂, CO₂, H₃PO₄, and KOH were used as an activated agent for activated carbon prepared from date palm. Among the activated carbons prepared by all the above activate agents, the activated carbon by ZnCl₂ exhibit the highest Hg uptake ability, followed by those by H₃PO₄ and KOH with a slight difference. The amount of Hg uptake for the activated carbon by CO₂, which is non-chemical activation, was lower than those by ZnCl₂, H₃PO₄ and KOH activated agents. It was clear that the amount of Hg uptake for the activated carbons prepared from date plam was 4-5 times larger than that for the commercial activated carbon, HG-S. In the present study, treatment time, concentration, adsorbent amount, and pH effects on the amount of Hg uptake were evaluated.

DOI： 10.11523/sekiyu.2015f.0_143

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Electrochemical Society Inc.  

Bimetallic Ni&lt
inf&gt
1-x&lt
/inf&gt
Fe&lt
inf&gt
x&lt
/inf&gt
/SDC powders containing 20wt% Ni-Fe were prepared and their anodic properties for SOFC were evaluated. The impedance spectra of the Ni&lt
inf&gt
1-x&lt
/inf&gt
Fe&lt
inf&gt
x&lt
/inf&gt
/SDC anodes at 800°C consisted of the ohmic component, R&lt
inf&gt
ohmic&lt
/inf&gt
, and depressed arcs, R&lt
inf&gt
HF&lt
/inf&gt
and R&lt
inf&gt
LF&lt
/inf&gt
. The R&lt
inf&gt
ohmic&lt
/inf&gt
component was due to the solid electrolyte layer, (ScO&lt
inf&gt
1.5&lt
/inf&gt
)&lt
inf&gt
0.18&lt
/inf&gt
(CeO&lt
inf&gt
2&lt
/inf&gt
)&lt
inf&gt
0.01&lt
/inf&gt
(ZrO&lt
inf&gt
2&lt
/inf&gt
)&lt
inf&gt
0.81&lt
/inf&gt
. The R&lt
inf&gt
HF&lt
/inf&gt
component was significantly reduced by the Fe addition, but apparent dependence was not observed for the R&lt
inf&gt
LF&lt
/inf&gt
component. The x=0.5 composition possessed the small R&lt
inf&gt
HF&lt
/inf&gt
and R&lt
inf&gt
LF&lt
/inf&gt
values. Accordingly, the single cell performance at 800°C was the maximum at x=0.5, and that was in the order of x=0.5 ≈ 0.2 &gt
0.8 ≈ 0 &gt
1.0. The mean crystallite size of Ni-Fe alloy increased approximately in this order. Therefore, we concluded that Fe addition to Ni decreases the particle size of Ni-Fe alloy, resulting in the enhancement of the catalytic activity of Ni&lt
inf&gt
1-x&lt
/inf&gt
Fe&lt
inf&gt
x&lt
/inf&gt
/SDC anode.

DOI： 10.1149/06801.1427ecst

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2015f.0_141

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK  

2,6-Pyridinedicarboxylic acid (H-2 dipic) reacts with copper-exchanged zeolite NaY to form [Cu(dipic)(H2O)(2)](n), which is encapsulated in the pores of the zeolite. In this zeolite-encapsulated form, the copper derivative functions as an efficient catalyst for the oxidation of cyclohexene, toluene, cyclohexane, and ethyl benzene in the presence of hydrogen peroxide (as an oxidant). The catalyst was readily recovered from the reaction mixture, and it could be reused for an additional three runs without perceptible loss of activity. The heterogeneous catalyst exhibited considerably higher activity and selectivity compared with [Cu(dipic)(H2O)(2)](n) itself.

DOI： 10.3906/kim-1408-42

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Influence of coexisting Al2O3 on the catalytic activity for low-temperature water-gas-shift (LT-WGS) reaction over Cu catalyst was investigated. The catalytic activity of Cu/Al2O3 catalyst increased with decreasing mesopore size when S/C ratio was 2.2, whereas the catalytic activity with S/C ratio = 4.6 increased with increasing mesopore size. IR measurement combined with kinetic study suggested that the low catalytic activity of Cu/CeO2 catalyst comes from the restriction of CO adsorption on Cu-0 by bidentate-type carbonate formed on the strong basic site of CeO2 support. On the other hand, it was found that bidentate-type carbonate was not formed on Cu/Al2O3 showing high catalytic activity for LT-WGS reaction. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2014.07.021

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Ni-impregnated SDC powders were prepared as a SOFC anode material. Surface area of the SDC powders was regulated with pre-calcination temperature and it was ranging from 12 to 93 m(2)/g. The averaged Ni particle size on SDC was fairly affected with surface area of the SDC supports. The smallest Ni particle size obtained in this study was 48 nm when the surface area of SDC was 27 m(2)/g. By further increasing the surface area of SDC to 93 m(2)/g, Ni particle size was adversely enlarged. The maximum power density increased with decreasing the averaged Ni particle size of Ni/SDC anode. The maximum power densities were 39.5 mWcm(-2) for dry H-2 and 106.5 mWcm(-2) for dry CH4. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2014.02.012

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2014f.0_97

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Materials Research Society  

Both Ni and alkaline earth metal oxide (MO: CaO, SrO, and BaO)-impregnated SDC powders were prepared as an SOFC anode material. The averaged Ni particle size on SDC was affected by the kind of alkaline earth metal oxide added. The addition of SrO and BaO to Ni/SDC anode enhanced power densities of both H2-SOFC and CH4-SOFC and the addition of CaO lowered them. The maximum power density increased with decreasing the averaged Ni particle size of Ni-MO/SDC anode.

DOI： 10.1557/opl.2014.815

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK  

A new magnetically separable catalyst consisting of binuclear Mn(II) complex [Mn-2 (HL)(2) (H2O)(4)], HL = 2-[(2-hydroxy-benzylidene)-amino]-3-(4-hydroxyphenyl)-propionic acid, supported on (3-chloropropyl)-trimethoxysilane (CPTMS) functionalized silica-coated magnetic nanoparticles (MNPs) was prepared. The synthesized catalyst was characterized by several physico-chemical and spectroscopic methods. This immobilized complex was found to be an efficient heterogeneous catalyst for the oxidation of different sulfides and hydrocarbons using hydrogen peroxide (H2O2) as an oxidant. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no considerable loss of catalytic activity.

DOI： 10.3906/kim-1307-50

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

A Schiff base ligand was synthesized by the condensation of salicylaldehyde with l-tyrosine. Interaction of this ligand with Mn(II)-exchanged zeolite Y leads to encapsulation of the ligand within the zeolite and complexation of the metal. The encapsulated complex has been characterized by spectroscopic studies and chemical analyses. This material serves as a catalyst for the oxidation of cyclohexene to cyclohexene epoxide and 2-cyclohexene-1-ol using H2O2 as oxidant. The reaction conditions have been optimized for solvent, temperature and amount of oxidant and catalyst. The catalyst shows high activity and selectivity toward production of cyclohexene epoxide in acetonitrile at 60 A degrees C with [H2O2]/[C6H10] = 2.5 molar ratio. Comparison of the encapsulated catalyst with the corresponding homogeneous catalyst showed that the heterogeneous catalyst had higher activity and selectivity than the homogeneous catalyst.

DOI： 10.1007/s11243-013-9742-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Influence of metal oxide added to Cu catalysts on the catalytic activity of the low-temperature water-gas-shift (LT-WGS) reaction was investigated. Catalytic activity was linearly correlated with both surface area of metallic copper (Cu-0) and surface Cu content in the identical copper-metal oxide system. However, activity per Cu-0 surface area changed depending on the metal oxide added. CO2-TPD profile demonstrated that the amount of strong basic sites on Cu-ZnOx and Cu-AlOx catalysts with high activity LT-WGS reactions was much less than those on Cu-FeOx and Cu-CeOx catalysts with low activity. Activity per Cu-0 surface area increased with increasing amount of weak basic sites on Cu-AlOx and Cu-ZnOx catalysts. From these results, it is suggested that in addition to Cu-0 surface area, basicity of a catalyst is one of the factors controlling the catalytic activity of Cu-based catalysts for LT-WGS reaction. (C) 2012 Published by Elsevier B. V.

DOI： 10.1016/j.cattod.2012.03.064

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Two kinds of heterometal coordination polymer precursors, {Sm[M(ox)(3)]center dot nH(2)O}, (M = Fe and Co), were prepared by the reaction of K-3[M(ox)(3)]center dot 3H(2)O with Sm(NO3)(3)center dot nH(2)O in methanol solvent. These compounds were found to have oxalato-bridged network structure. On the other hand, the desired heterometal coordination polymer precursors could not be obtained by the present preparation method using water solvent. The thermal decomposition behaviors of these d-f heterometal coordination polymer precursors were investigated under air atmosphere. The perovskite-type oxides, SmMO3 (M = Fe and Co), were found to form in the temperature range of >600 degrees C. The specific surface area of SmFeO3 powder increased with decreasing calcination temperature of Fe-containing heterometal coordination polymer precursor. (C)2013 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.121.84

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2013f.0_156

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：JAPAN PETROLEUM INST  

Metal-supported active carbon adsorbents were applied to remove the small amount of H2S contained in biogas CH4. H2S adsorption experiments using column type-equipment demonstrated that copper-supported active carbon exhibited high H2S adsorption ability. From the practical point of view, the width and the rate of the adsorption layer were estimated using copper-supported active carbons. Assuming that the metal ion was initially coordinated with oxygen atoms in H2O molecules, the energy change in substituting a H2O molecule by a H2S molecule was calculated using a calculation program for the ab initio molecular orbital method (Gaussian 09). The results of these energy calculations suggest that Cu-0 and Cu+ species have the highest adsorption affinity with H2S among various metal and metal ions, in agreement with the present experimental results.

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Bi-layered cathodes with the LSM/LSM-YSZ structure for solid oxide fuel cells were successfully formed on the carbon-sputtered surface of a YSZ sheet by electrophoretic deposition (EPD). The thicknesses of the first layer of LSM-YSZ (LY) and the second layer of La0.8Sr0.2MnO3 (LSM) could be controlled by adjusting the deposition time in the EPD process. The cathodic properties of the bi-layered structures were superior to those of the mono-layered structures, and were dependent on the thickness of each layer. Decreasing the thickness of the first layer and increasing that of the second layer tended to reduce both polarization and ohmic resistances. The optimal thickness of the first layer at the operating temperature of 600 degrees C was 4 mu m, suggesting that an effective three-phase boundary was extended from the interface between the electrolyte and cathode film to around 4 mu m thickness. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jpowsour.2012.04.079

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Two sets of adsorbents were prepared from locally available raw materials, characterized and tested. The first set consists of crushed natural attapulgite and crushed attapulgite mixed with petroleum tank-bottom sludge and carbonized at 650 degrees C. Another set was prepared using trunk of date palm tree (Phoenix dactylifera) activated at 700 and 800 degrees C. Both sets were characterized using BET surface area and pore distributions, FTIR, XRD, SEM and TEM. Natural attapulgite and attapulgite/sludge composite exhibited different characteristics and adsorptive capacities for oil removal from oily water. Adsorptive capacities were calculated from the breakthrough curves of a column test. An oily water solution of about 500 mg-oil/L was passed through both the attapulgite and attapulgite/sludge columns until the column effluent concentration exceeded a reference limit of 10 mg-oil/L. Uptake,was calculated at this limit at 155 and 405 mg-oil/g-adsorbent, respectively. This was lower than the performance of a commercial activated carbon sample (uptake calculated at 730 mg-oil/g-adsorbent). Relatively, the date palm, carbonaceous-based adsorbent samples showed less significant differences in both bulk and surface properties. Uptake significantly improved to 1330-1425 mg-oil/g-adsorbent. Attempt was made to associate this performance with the difference in the surface areas between the two sets. However, other factors are found to be important as the second set has a range of surface area less than that of the commercial sample. As evidenced by FTIR, XRD and TEM, the activated carbonaceous materials developed porous structures which form defective graphitic sheet ensembles that serve as additional adsorption sites in the sample. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jaap.2012.04.003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The selective hydroxylation of cyclohexene to 2-cyclohexen-1-ol with hydrogen peroxide in water was successfully achieved using [Fe(bpy)(3)](2+) complexes encapsulated into Y-type zeolite.

DOI： 10.1246/cl.2012.713

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The influence of A-site lanthanoids in the perovskite-type oxide catalysts, LnFe(x)Co(1-x)O(3) (Ln = La, Pr, Sm, Gd, Dy, Ho, Er, and Yb), prepared by the thermal decomposition of cyano complexes, Ln[FexCo1-x(CN)(6)]center dot nH(2)O, on the catalytic activity of CO oxidation was investigated. Using XRD, N-2 adsorption, SEM, XPS, and H-2-temperature programmed reduction (TPR) techniques, it was found that A-site lanthanoid ions in perovskite-type oxide LnFeO(3) affect the formation temperature of single phase, the crystalline structure, and the size of perovskite-type oxide particles. The catalytic activity of LnCoO(3) was improved by the replacement of Co ion with Fe ion regardless of the kind of A-site lanthanoid ion. A-site lanthanoids in perovskite-type oxide also affect the reducibility of B-site Co ion in LnFe(0.5)Co(0.5)O(3), leading to the change in the catalytic property. TPR results of LnFe(0.5)Co(0.5)O(3) suggest that the reducibility of Co ion is related to the distortion of perovskite structure. (C) 2011 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.cattod.2011.09.023

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

FeOx-promoted Cu/Al2O3 catalysts active for low-temperature water-gas-shift (LT-WGS) reaction, reported previously (H. Yahiro, K. Sagata, T. Yamamoto, K. Saiki, M. Asamoto, H. Yamaura, Catal. Lett. 2008, 124, 233.), were characterized by TPR, TPO, XRD, and XPS measurements. These techniques proved that Fe2O3 was partially reduced by H-2 to Fe3O4 at 573 K in the presence of Cu-0 and that the obtained Fe3O4 was reoxidized by O-2 at the same temperature. The pronounced effect of Fe addition to Cu/Al2O3 on the catalytic activity for WGS reaction was observed at 523-623 K. It is concluded that partially reduced Fe2O3, probably Fe3O4, acts as an active site for LT-WGS reaction in the addition to Cu-0, resulting in the improvement of the catalytic activity at 523-623 K.

DOI： 10.1246/bcsj.20110283

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2012f.0_113

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Language：Japanese   Publishing type：Research paper (scientific journal)  

Metal-supported active carbon adsorbents were applied to remove the small amount of H2S contained in biogas CH4. H2S adsorption experiments using column type-equipment demonstrated that copper-supported active carbon exhibited high H2S adsorption ability. From the practical point of view, the width and the rate of the adsorption layer were estimated using copper-supported active carbons. Assuming that the metal ion was initially coordinated with oxygen atoms in H2O molecules, the energy change in substituting a H2O molecule by a H2S molecule was calculated using a calculation program for the ab initio molecular orbital method (Gaussian 09). The results of these energy calculations suggest that Cu0 and Cu+ species have the highest adsorption affinity with H2S among various metal and metal ions, in agreement with the present experimental results.

DOI： 10.1627/jpi.55.371

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2012f.0_33

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Catalytic mechanism of ethylbenzene dehydrogenation over Fe-Co/Mg(Al)O derived from hydrotalcites has been studied based on the XAFS and XPS catalyst characterization and the FTIR measurements of adsorbed species. Fe-Co/Mg(Al)O showed synergy, whereas Fe-Ni/Mg(Al)O showed no synergy, in the dehydrogenation of ethylbenzene. Ni species were stably incorporated as Ni(2+) in the regular sites in periclase and spinel structure in the Fe-Ni/Mg(Al)O. Contrarily, Co species exists as a mixture of Co(3+)/Co(2+) in the Fe-Co/Mg(Al)O and was partially isolated from the regular sites in the structures with increasing the Co content. Co addition enhanced Lewis acidity of Fe(3+) active sites by forming Fe(3+)-O-Co(3+/2+)(1/1) bond, resulting in an increase in the activity. FTIR of ethylbenzene adsorbed on the Fe-Co/Mg(Al)O clearly showed formations of C-O bond and pi-adsorbed aromatic ring. This suggests that ethylbenzene was strongly adsorbed on the Fe(3+) acid sites via pi-bonding and the dehydrogenation was initiated by alpha-H(+) abstraction from ethyl group on Mg(2+)-O(2-) basic sites, followed by C-O-Mg bond formation. The alpha-H(+) abstraction by O(2-)(-Mg(2+)) was likely followed by beta-H abstraction, leading to the formations of styrene and H(2). Such catalytic mechanism by the Fe(3+) acid-O(2-)(-Mg(2+)) base couple and the Fe(3+)/Fe(2+) reduction-oxidation cycle was further assisted by Co(3+)/Co(2+), leading to a good catalytic activity for the dehydrogenation of ethylbenzene. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcata.2011.08.032

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

The carbon oxidation over copper ion-exchanged zeolites (Cu-MFI, Cu-MOR, Cu-FAU, and Cu-BEA) pretreated at 700 A degrees C was investigated. The catalytic activities of Cu-MFI, Cu-MOR, and Cu-FAU pretreated at 700 A degrees C were higher for carbon oxidation in NO + O(2) atmosphere than that of Cu-BEA. The TEM results demonstrated that Cu fine particles were formed on the external surface of Cu-MFI, Cu-MOR, and Cu-FAU, showing high activity. In addition, it was suggested that the coexisting NO plays an important role in enhancing the catalytic activity of Cu-MFI for carbon oxidation.

DOI： 10.1007/s11164-011-0381-0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The thermal decomposition reaction of crystalline heteronuclear cyano complex precursor to crystalline perovskite-type oxide catalyst was investigated. From X-ray single crystal analysis and XRD, FT-IR, TG-DTA, SEM, and BET measurements, the thermal decomposition process of Sm[Fe(CN)(6)]center dot 4H(2)O precursor was elucidated. It was found that the specific surface area of SmFeO3 decreased monotonously with increasing calcination temperature of Sm[Fe(CN)(6)]center dot 4H(2)O, while the highest catalytic activity for CO oxidation was achieved for Sm[Fe(CN)(6)]center dot 4H(2)O calcined at 600 degrees C. The size of Sm[Fe(CN)(6)]center dot 4H(2)O precursor depended on the molar concentration of starting materials, Sm(NO3)(3)center dot 6H(2)O and K3Fe(CN)(6), in aqueous solution (C-s); the size of Sm[Fe(CN)(6)]center dot 4H(2)O decreased with decreasing C-s. The decrease in particle size of cyano complex was found to result in the increase in specific surface area of perovksite-type oxide obtained after calcination. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2011.04.048

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A series of Mg3-xZnxFe0.5Al0.5 mixed oxide catalysts derived from hydrotalcites were tested in the ethylbenzene dehydrogenation to styrene in He atmosphere at 550 degrees C. The catalysts were prepared by coprecipitation from the nitrates of metal components followed by calcination to mixed oxides at 550 degrees C. A part of Mg2+ in Mg3Fe0.5Al0.5 mixed oxide was replaced with Zn2+ to test the effect of MgO as the support. The mixed oxides were composed of periclase and spinel-type compounds with a high surface area of 100-180 m(2) g(cat)(-1) Mossbauer and XPS measurements indicated the presence of Fe3+ on the catalysts and H-2-TPR measurement suggested that the dehydrogenation reaction is catalyzed by the reduction-oxidation between Fe3+/Fe2+. The activity of Mg3-xZnxFe0.5Al0.5 mixed oxide decreased with increasing x, indicating an important role of MgO on the activity. Both CO2-TPD measurements as well as IR measurements of adsorbed CO2 clearly indicated the presence of basic sites of Mg2+O2- on the catalysts. It seems that the combination of Mg2+O2- and Fe3+ was essential for the catalytic activity. It is concluded that the surface base sites generated on O2- bound Mg2+ near Fe3+ sites are responsible for H+-abstraction; the dehydrogenation of ethylbenzene was initiated by the H+ abstraction on Mg2+O2- basic sites, and accelerated by the reduction-oxidation of Fe3+/Fe2+ active species. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcata.2011.03.023

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A series of Mg3Fe0.5-xCoxAl0.5 (x=0-0.5) catalysts were prepared from hydrotalcite precursors and their activities in the dehydrogenation of ethylbenzene were compared with those of a series of Mg3Fe0.5-yNiyAl0.5 (y = 0-0.5) catalysts also derived from hydrotalcite. The hydrotalcites prepared by co-precipitation were calcined at 550 degrees C to the mixed oxides with a high surface area of 150-240 m(2) g(cat)(-1); they were composed of Mg(Fe,Me,Al)O periclase and Mg(Me)(Fe,Al)(2)O-4 spinet (Me = Co or Ni). Bimetallic Fe3+-Co2+ system showed a synergy, i.e., an increase in the activity, whereas Fe3+-Ni2+ bimetallic system showed no synergy. The high styrene yield was obtained on Mg3Fe0.1Co0.4Al0.5; however, a large substitution of Fe3+ with Co2+ caused a decrease in styrene selectivity along with coking on the catalysts, due to an isolation of CoOx on the catalyst surface. The highest yield as well as the highest selectivity for styrene production was obtained at x = 0.25 at time on stream of 30 min. The coprecipitation at pH = 10.0 and the composition of Mg3Fe0.25Co0.25Al0.5 were the best for preparing the active catalyst. This is partly due to the formation of a good hydrotalcite structure. On this catalyst, the active Fe3+ species was reduced at a low temperature by the Fe3+-Co2+ bimetal formation, leading to a high activity. Simultaneously, the amount of reducible Fe3+ was the smallest, resulting in a high stability of the active Fe3+ species. It is likely that the dehydrogenation was catalyzed by the reduction-oxidation between Fe3+ and Fe2+ and that Co2+ assisted the reduction-oxidation by forming Fe3+-Co2+ (1/1) bimetallic active species. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcata.2011.02.003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The CO sensing property of CuO-loaded SnO2-In2O3 sensor was investigated in a reducing atmosphere. The sensor response to CO for CuO/SnO2-In2O3 (8/2) was much higher than that for CuO/SnO2 in the range of 200-1000 ppm of CO concentration. Such a high sensor response of CuO/SnO2-In2O3 may originate from the high dispersion of CuO playing a role as sensing site. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2010.10.044

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The electrochemical performances of proton-conducting SOFCs with the perovskite-type oxide cathodes were investigated at low temperature of 773 K. Among the perovskite-type oxides used in the present study. La(0.7)Sr(0.3)FeO(3) (LSF) cathode exhibited the lowest overpotential at 773 K. The power density of the SOFC was dependent on the particle size of LSF cathode. The decrease in the particle size resulted in the decrease in over potential. The Power density of the cell with LSF cathode was also dependent on the thickness of LSF cathode; in the present condition, the LSF cathode with 13-mu m thickness showed the best electrochemical performance at 773 K. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jpowsour.2010.08.002

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2011f.0.197.0

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2011f.0.96.0

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DOI： 10.11523/sekiyu.2011f.0.168.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A series of FeOx-MeOy/Mg(Al)O catalysts were prepared from hydrotalcite-like compounds as precursors and were tested in the ethylbenzene dehydrogenation to styrene in He atmosphere at 550 degrees C The hydrotalcite-like precursors of the metal compositions of Mg3Fe0 25Me0 25Al0 5 (Me = Cu Zn Cr Mn Fe Co and Ni) were coprecipitated from the nitrates of metal components and calcined to mixed oxides at 550 C After the calcination the mixed oxides showed high surface area of 150-200 m(2) g(cat)(-1) and were mainly composed of (MgMe)(Fe3+ Al)O penclase in the bulk whereas the surface was enriched by (MgMe)(Fe3+ Al)(2)O-4 pinel Among the Me species tested Co2+ was the most effective followed by Ni2+ Co2+ addition increased the activity of original FeOx/Mg(Al)O catalyst whereas Ni2+ increased the activity at the beginning of reaction but deactivated the catalyst during the reaction The other metals formed isolated MeOx species in the catalyst resulting in a decrease in the activity compared to the original FeOx/Mg(Al)O catalyst The active Fe species exists as metastable Fe3+ on the FeOx/Mg(Al)O catalyst By the addition of Co2+ the reduction-oxidation between Fe3+ and Fe2+ was facilitated and moreover the active Fe3+ species was stabilized It is likely that the dehydrogenation proceed on the active Fe3+ species via its reduction-oxidation assisted by Co2+ (C) 2010 Elsevier B V All rights reserved

DOI： 10.1016/j.apcata.2010.10.017

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The photocatalytic reaction in the partial oxidation of alpha-methylstyrene (alpha-MS) to acetophenone (AP) was investigated for TiO(2) supported on H-ZSM-5 (H-MFI), H-mordenite (H-MOR), and H-Y-type (H-FAU) zeolites. XRD results demonstrated that the anatase was the stable phase of TiO(2) supported on zeolites. Photocatalytic activities of supported catalysts decreased in the following order: TiO(2)/H-MFI "TiO(2)/H-MOR > (TiO(2)) > TiO(2)/H-FAU" (blank). TiO(2)/H-MFI catalyst exhibited the best performance for photocatalytic oxidation of alpha-MS to AP. The maximal activity was obtained by 25 wt% TiO(2)/H-ZSM-5. The addition of water to the reaction solvent resulted in significantly lowering the photocatalytic activity for TiO(2)/H-ZSM-5 catalyst, although its activity for TiO(2) and TiO(2) + H-ZSM-5 mechanical mixture was little influenced by the amount of water added to reaction solvent. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.electacta.2009.11.091

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

Pt catalysts supported on Al(2)O(3) beads prepared by a sputter deposition method showed the higher surface concentration of Pt than impregnated Pt catalysts. The catalytic activities of the oxidation of acetylene carbon black over the sputtered Pt catalysts were higher than those over the impregnated Pt catalysts with the same Pt content.

DOI： 10.1007/s11244-010-9500-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The carbon oxidation was investigated over copper ion-exchanged MR zeolite (Cu-MFI) as a function of pretreatment temperature. Cu-MR pretreated at 700 degrees C exhibited high activity for carbon oxidation in NO + O(2) atmosphere. The activity of Cu-MFI pretreated at 700 degrees C increased with increasing the amount of copper ion exchanged. XRD and ESR measurements suggest that the CuO fine particles as an active site for carbon oxidation were formed on the surface of MR zeolite by pretreatment at 700 degrees C. (C) 2010 Elsevier By. All rights reserved.

DOI： 10.1016/j.catcom.2010.02.025

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Phase separation in an acidic aqueous solution with sodium silicate and sodium dodecyl sulfate (SDS) was investigated. The solution separated into silica-rich and SDS-rich phases during condensation of silica components. During the phase separation, the transition structure was fixed by gelation, resulting in mutually continuous morphology. The addition of a small amount of water-miscible organic solvents, such as methanol, ethanol, 1-propanol, and 1-butanol, into the reacting solution greatly decreases both viscosity and phase separation tendency of the solution. In the system with high concentration of strong acid. SDS molecules form wormlike micelles, which not only increase viscosity of the solution hut also play an important role in the phase separation in the solution because the to of wormlike micelles increases apparent molecular weight of SDS and decreases mixing entropy. The decrease in the viscosity by the addition of organic solvents suggests that wormlike in become small in the presence of organic solvent molecules. Consequently, the addition of appropriate amount of organic solvent is effective for controlling phase separation tendency and size of the resulted macropores in the system with SDS through the change in the structure of the micelles. (C) 2010 The Ceramic Society of Japan All rights reserved

DOI： 10.2109/jcersj2.118.295

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Phase separation in an acidic aqueous solution with sodium silicate and sodium dodecyl sulfate (SDS) was investigated. The solution separated into silica-rich and SDS-rich phases during condensation of silica components. During the phase separation, the transition structure was fixed by gelation, resulting in mutually continuous morphology. The addition of a small amount of water-miscible organic solvents, such as methanol, ethanol, 1-propanol, and 1-butanol, into the reacting solution greatly decreases both viscosity and phase separation tendency of the solution. In the system with high concentration of strong acid. SDS molecules form wormlike micelles, which not only increase viscosity of the solution hut also play an important role in the phase separation in the solution because the to of wormlike micelles increases apparent molecular weight of SDS and decreases mixing entropy. The decrease in the viscosity by the addition of organic solvents suggests that wormlike in become small in the presence of organic solvent molecules. Consequently, the addition of appropriate amount of organic solvent is effective for controlling phase separation tendency and size of the resulted macropores in the system with SDS through the change in the structure of the micelles. (C) 2010 The Ceramic Society of Japan All rights reserved

DOI： 10.2109/jcersj2.118.295

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

CaO catalysts supported on several metal oxides and zeolites were investigated for transesterification of triolein with methanol. Zeolite-supported CaO catalysts showed high catalytic activity for transesterification compared to the metal oxide-supported CaO catalysts; among the zeolites tested in this work, mordenite exhibited the best support. The catalytic activity of mordenite-supported CaO catalyst depended on both the amount of CaO loading and the calcination temperature for catalyst precursor.

DOI： 10.1246/cl.2010.198

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS INC  

CO sensing properties of various transition metal oxide-loaded SnO2 sensors were investigated in a reducing atmosphere such as wet H2 gas. Among transition metal oxide-loaded SnO2 sensors used in the present study, CuO-loaded SnO2 sensor exhibited the highest sensor response to 1% CO in wet 50% H2 at around 150 degrees C, while it showed no sensor response in dry 50% H2. From X-ray diffraction (XRD) analysis, CuO was reduced to metallic Cu in a reducing atmosphere at above 150 degrees C. H2-temperature-programmed reduction (H2-TPR) and diffuse reflectance Fourier transform infrared (DRIFT-IR) spectroscopy measurements were carried out to discuss the sensor response mechanism.

DOI： 10.1080/10426911003750745

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It is well-known that the perovskite-type oxides exhibit high catalytic activity for oxidation reaction. The present paper concentrates on catalytic activity and surface composition of the perovskite-type oxide prepared by thermal decomposition of heteronuclear complex.

DOI： 10.1007/s10563-009-9079-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE INC  

The anodic performances of Ni/CeO(2)-Sm(2)O(3)(Ni/SDC) modified by the addition of alkaline earth metal oxides (MgO, CaO, and SrO) were investigated for direct oxidation of CH(4) in solid oxide fuel cells (SOFCs). Although the initial power density of cell with Ni/SDC anode modified by the addition of CaO was slightly lower than that of cell with Ni/SDC, the former anode exhibited an excellent stability compared to the latter one. Such a high stability of Ni-CaO/SDC anode may come from the inhibition of carbon deposition in addition to the retained ionic conductivity of anode. (c) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.elecom.2009.05.042

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

The perovskite-type SmFe (x) Co1-x O-3 oxides were prepared by the thermal decomposition of heteronuclear cyano complexes, Sm[Fe (x) Co1-x (CN)(6)] a (TM) nH(2)O. XRD studies demonstrated that SmFe (x) Co1-x O-3 catalyst prepared by the thermal decomposition of heteronuclear cyano complex at 1,273 K showed orthorhombic structure in whole range of x. The catalytic activity for CO oxidation was dependent on x in SmFe (x) Co1-x O-3; the maximum activity was obtained for SmFe0.5Co0.5O3.

DOI： 10.1007/s11244-009-9233-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC JAPAN  

The electrochemical performances of Proton-conducting SOFC with La0.7Sr0.3FeO3 (LSF) cathode fabricated by the electrophoretic deposition (EPD) technique were investigated. The EPD technique provided the uniform layer of LSF cathode with constant thickness and can easily control the thickness by changing all applied voltage. The power density of the SOFC cell was dependent on the thickness of LSF cathode. The activation energy was measured to elucidate the rate-determining, step for LSF cathode reaction.

DOI： 10.5796/electrochemistry.77.143

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The catalytic activities of the low-temperature water-gas-shift (LT-WGS) reaction were investigated for Al2O3-supported Cu catalysts containing CrOx, MnOx, FeOx, CoOx, NiOx, or ZnO. The catalytic activity of Cu/Al2O3 catalyst at 423 K was improved by the small addition of transition-metal oxide. fit particular, Cu/Al2O3 with CoOx showed the highest activity among the supported Cu catalysts used in this study.

DOI： 10.1246/cl.2009.172

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELECTROCHEMICAL SOC INC  

Electrolysis of aqueous glycerin using polymer electrolyte membrane (PEM) was investigated. Electrolysis of aqueous glycerin was achieved with lower applied cell voltage (0.4 V) than that of water and simultaneously hydrogen was produced from the cathode side. Electrolysis efficiency of aqueous glycerin was increased with an increase in operating temperature.

DOI： 10.1149/1.3210750

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELECTROCHEMICAL SOC INC  

The anodic performances of Ni/CeO2-Sm2O3(Ni/SDC) modified by the addition of alkaline earth metal oxides (MgO, CaO, SrO, and BaO) were investigated for direct oxidation of CH4 in solid oxide fuel cells (SOFCs). Although the initial power density of cell with Ni/SDC anode modified by the addition of CaO (Ni-CaO/SDC) was slightly lower than that of cell with Ni/SDC, the former anode exhibited an excellent stability compared to the latter one. After continuous operation of SOFC for 24 h, no or less amount of carbon deposition was observed over Ni-CaO/SDC.

DOI： 10.1149/1.3205764

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Language：English  

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Language：Japanese   Publisher：The Ceramic Society of Japan  

DOI： 10.14853/pcersj.2009F.0.2Q01.0

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Language：Japanese   Publisher：The Ceramic Society of Japan  

DOI： 10.14853/pcersj.2009F.0.2I26.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The electrochemical performances and the morphologies of Ni/SDC anodes fabricated by EPD technique were investigated for direct oxidation of dry CH(4) in solid oxide fuel cells (SOFCs). Ni/SDC(EPD) anode with both 20 wt% of Ni content and 20 mu m of thickness exhibited the lowest overpotential and the highest maximum power density for dry CH(4)-air SOFC at 973 K. The power density of the cell with Ni/SDC(EPD) anode was higher than that with Ni/SDC fabricated by a conventional slurry coating method. It was found that Ni/SDC(EPD) anode having dense structure suppressed carbon deposition and exhibited a stable cell operation in SOFC using dry CH(4). (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2008.08.027

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The perovskite-type SmFeO(3) powders were prepared by the four different methods, named decomposition method of heteronuclear cyano complexes (CN), polymer precursor method (PP), reverse micelle method (RM) and reverse homogenous precipitation method (RHP), and their catalytic activities were evaluated with a CO oxidation reaction. The surface areas and the surface chemical compositions of Sm, Fe, O and C were strongly dependent on the preparation methods and calcination temperatures. On the basis of such the characteristics on the surface the factors controlling the catalytic activity are discussed. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2008.08.014

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Among the supported Cu-FeO(x) catalysts, Al(2)O(3)-supported Cu-FeO(x) catalyst exhibited the highest activity for WGS reaction. The enhancement of the catalytic activity by adding FeO(x) to Cu/Al(2)O(3) could be interpreted by the two possibilities; one is the formation of highly dispersed Cu(0) and the other is the participation of reduced FeO(x) in WGS reaction in the presence of Cu(0).

DOI： 10.1007/s10562-008-9504-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Solid-state electrochemical sensors for volatile organic compounds (VOCs) based on commercial yttria stabilized zirconia (YSZ) sheet were fabricated using Pt or Pt covered with SmFeO3 layers as electrodes. The sensing performances were strongly influenced by the surface morphology of YSZ. The overcoat with SmFeO3 layer on the one side electrode enhanced the sensitivity for some VOCs. Even for 0.5 ppm of methyl ethyl ketone, ethanol and acetic acid, the changes of the electromotive force (EMF) in the levels of 20 mV and higher were confirmed at 400 degrees C for the monolithic type sensor in which one side electrode was over-coated with SmFeO3 powders. (C) 2008 The Ceramic society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.116.777

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：TRANS TECH PUBLICATIONS LTD  

CO sensing properties of various transition metal oxide-loaded SnO2 sensors were investigated in a reducing atmosphere such as wet H-2 gas. Among transition metal oxide-loaded SnO2 sensors used in the present study, 5wt%CuO-loaded SnO2 sensor exhibited the highest sensitivity to 1% CO in wet 50% H-2 at around 150 degrees C, while it showed no sensitivity in dry 50% H-2. From XRD analysis, CuO was reduced to metallic Cu in a reducing atmosphere at above 150 degrees C. H2-temperature-programmed reduction (H-2-TPR) and diffuse reflectance fourier transform infrared (DRIFT-IR) spectroscopy measurements were carried out to discuss the sensor response mechanism.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：CRC PRESS-TAYLOR & FRANCIS GROUP  

The electrochemical performances of the perovskite-type oxide cathode with uniform particles were investigated in H(2)-O(2) SOFC system using proton conductor. Among the perovskite-type oxides used in the present study, La(0.7)Sr(0.3)FeO(3) (LSF) exhibited the lowest cathodic overpotential at the temperature as low as 773 K. It was found that the overpotentials of LSF cathode and the activation energies of cathode reaction were influenced by the electrode morphologies such as particle size and uniformity. The electrophoretic deposition (EPD) as a new method was applied to fabricate the LSF cathode on electrolyte surface.

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Language：Japanese   Publisher：The Ceramic Society of Japan  

DOI： 10.14853/pcersj.2008F.0.683.0

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：CRC PRESS-TAYLOR & FRANCIS GROUP  

The catalytic activities of the low-temperature water-gas-shift (WGS) reaction were investigated for Al(2)O(3)-supported Cu catalysts containing CrO(x), MnO(x), FeO(x), CoO(x)., or NiO(x). The catalytic activity of Cu/Al(2)O(3) catalyst at 423 K was enhanced by the addition of transition metal oxide. FeO(x) and MnO(x) additives additionally gave the enhancement in the catalytic activity at 523 K. The preparation conditions concerning calcination temperature and MOx/Cu molar ratio were optimized for Cu-FeO(x)/Al(2)O(3) and Cu-CoOx/Al(2)O(3) catalysts. The reason why the catalytic activity was enhanced by adding Fe Ox and CoO(x) to Cu/Al(2)O(3) was proposed on the basis of XRD and H(2)-TPR results.

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2008f.0.72.0

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Language：Japanese   Publisher：The Ceramic Society of Japan  

DOI： 10.14853/pcersj.2008F.0.717.0

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Language：Japanese   Publisher：The Ceramic Society of Japan  

DOI： 10.14853/pcersj.2008F.0.493.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

This paper presents a study on the influence of support (Al2O3, MgO, SiO2-Al2O3, SiO2-MgO, beta-zeolite, and CeO2) of Cu-ZnO catalysts for the low-temperature water-gas shift reaction. Supported Cu-ZnO catalysts were prepared by the conventional impregnation method, followed by the H-2 reduction. The activity of Cu-ZnO catalysts for the water-gas shift (WGS) reaction was largely influenced by the kind of support; Cu-ZnO catalysts supported on Al2O3, MgO, and CeO2 showed high activity, while those on SiO2-Al2O3, SiO2-MgO and beta-zeolite showed less activity in the temperature range 423-523 K. XRD analysis demonstrated that the copper species were highly dispersed on the supports used in the present study, except for a MgO support. TPR results of a series of supported CuO-ZnO catalysts suggest that the reducibility of CuO is one of the important factors controlling the activity of the WGS reaction over the supported catalysts. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2007.06.020

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The decomposition activities of nitrogen monoxide (NO) were investigated for the copper ion-exchanged ZSM-5 zeolites (Cu-MFI) containing the rare-earth elements: La, Ce, Pr, Nd, Sm, and Gd. It was found that Sm and Gd acted as promoter for NO decomposition over Cu-MFI with 60-70% of the exchange level of copper ion, while the addition of the other rare-earth elements to Cu-MFI showed no positive effect on NO decomposition activity. The introduction of Sm and Gd to Cu-MFI had little influence on the effectiveness of each copper ion for NO adsorption in the MFI zeolite. The presence of Sm and Gd stabilized Cu+ as an active center. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2007.06.003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The photocatalytic reaction in the partial oxidation of a-methylstyrene (alpha-MS) to acetophenone (AP) was investigated for TiO2 supported on Y-type, moredenite, and ZSM-5 zeolites. XRD and FT-Raman results demonstrated that the anatase is the stable phase of TiO2 supported on zeolites and no rutile phase was observed in the supported catalysts calcined at 723-973 K. TiO2 supported on zeolites was found to catalyze the partial oxidation of a-MS to AP under light irradiation (> 290 nm). The photocatalytic activity of TiO2 supported on zeolites was significantly improved by the addition of the water to the organic solvent. It was found that the optimized amount of water added for TiO2 supported on zeolite catalysts was smaller than that for TiO2 catalyst. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2006.07.039

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELECTROCHEMICAL SOC INC  

The anode performances of Ni/(CeO2)(1-x)(LnO(1.5))(x) (Ln: La, Pr, Nd, Sm, Gd, and Yb) were investigated in direct-methane solid oxide fuel cells. Among the anodes tested in the present study, Ni/CeO2-Sm2O3 and Ni/CeO2-Yb2O3 composite anodes showed relatively low anodic overpotential. The anodic overpotential of Ni(x wt%)/(CeO2)(1-y)(SmO1.5)(y) depended strongly on Ni content, while it less depended on Sm content. The catalytic activity of methane oxidation was measured for Ni/LnDC at 973 K and Ni/CeO2 and Ni/CeO2-Yb2O3 samples showed high catalytic activity. This result suggests that the activity for the direct oxidation of methane by O-2 is not the main factor controlling the anodic overpotential in direct-methane solid oxide fuel cell.

DOI： 10.1149/1.2729281

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

The electrochemical performances were investigated for proton-conducting solid oxide fuel cells (SOFCs) with the perovskite-type oxide cathodes. As for proton-conducting SOFC using BaCe0.8Y0.2O3 (BCYO) and SrCe0.95Yb0.05O3 (SCYO) electrolytes, La0.7Sr0.3O3 (LSFO) cathode showed the best electrochemical performance among the perovskite-type oxides tested in the present study. The spin-coating technique was applied to fabricate BCYO thin film on the LSFO substrate. With this technique, dense and crack-free BCYO thin film could be fabricated on LSFO electrode substrate. However. the electrical conductivity of BCYO thin film fabricated on LSFO electrode substrate was lower than that of the bulk BCYO specimen. suggesting the formation of the second phase between the electrolyte film and the oxide substrate. (c) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2007.02.116

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：MATERIALS RESEARCH SOC  

The cathode performances of perovskite-type oxide electrodes were investigated in the H-2-O-2 fuel cell with proton-conducting electrolyte. Among the perovskite-type oxides tested in the present study, La1-xSrxFeO3 (LSFO) showed the best cathode performance. The cathode performances of LSFO depended on the Sr content and the heat-treatment temperature prior to electrochemical measurements. The cathode reactions of both LSFO and Pt electrodes are discussed briefly based on the cathode overpotentials measured as a function of oxygen partial pressure. Finally, the structure and the electrical conductivity of the proton-conducting ceramic film fabricated on LSFO electrode substrate are presented.

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2007f.0.4.0

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2007f.0.142.0

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELECTROCHEMICAL SOC INC  

Metal wire meshes were coated with electrode materials such as La0.8Sr0.2NbO3 and NiO/YSZ by electrophoretic deposition (EPD) and used as current collectors for a solid oxide fuel cell. The current interrupt analysis for the electrodes attached with the wire mesh current collectors clearly indicated that coated wire meshes remarkably reduced the cathodic and anodic resistances, especially polarization component, compared to using the uncoated meshes. This reduction of the electrode resistances is due to the fact that EPD coating of the metal meshes increases effective contact area and/or points between the wire mesh and electrode surface. A single cell with the EPD coated meshes exhibited higher I-V characteristics compared to that with the uncoated meshes as expected from the result of the electrode resistance measurements.

DOI： 10.1149/1.2729235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Manganese-doped ceria-based oxides, Ce1-xMnxO2-delta (0.05 <= x <= 0.3) and Ce1-x-yGdxMnyO2-delta (0.05 <= x <= 0.2, 0.05 <= y <= 0.25) were synthesized, and crystal phase analysis by XRD and measurements of electrical properties were performed. Solubility limit of Mn in Ce1-xMnxO2-delta seemed to be between 5 mol% and 10 mol% and Mn3O4 Was the main by-product above the solubility limit in the case of heat treatment at 1300 degrees C. Judging from the oxygen partial pressure dependence of total conductivity and emf measurements, Ce1-xMnxO2-delta is a single-phase mixed conductor within the composition below the solubility limit, and when the composition of Mn exceeds the solubility limit, it becomes the dual-phase mixed conductor of Ce1-xMnxO2-delta and Mn3O4. The doing of Mn in gadlia-doped ceria, Ce1-x-yGdxMnyO2-delta (0.05 <= x <= 0.2, 0.05 <= y <= 0.25), was more difficult than that in CeO2 presumably due to the preferential reaction between Gd and Mn to give GdMnO3 to the GDC solid solution formation, and the Mn doping seems not to be so effective in preparing the mixed ionic-electronic conductor based on GDC. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2006.04.016

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Language：Japanese  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The effect of calcination temperature on the catalytic activity for water-gas-shift (WGS) reaction was investigated for copper/alumina catalysts prepared by the impregnation method. The catalyst calcined at 1073 K, followed by the treatment in H-2 at 523 K, showed a high activity for WGS reaction. XRD and H-2-TPR measurements revealed that the catalyst calcined at 1073 K contained both highly dispersed CuO and spinel CuAl2O4 particles. The former species was reduced by the treatment in H? at 523 K to yield the highly dispersed metallic copper which would act as catalytically active sites in WGS reaction. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2005.11.004

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2006f.0.4.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Copper (11) phthalocyanine (CuPc) molecules encapsulated into zeolite-Y with Si/Al ratios of 2.7 and 410 were prepared by an in situ synthesis and characterized by UV-Vis and electron paramagnetic resonance (EPR) spectroscopies. Resolved Cu-hyperfine and N-superhyperfine structures were observed in the EPR spectrum of CuPc encapsulated into zeolite-Y with a high Si/Al ratio. UV-Vis and EPR studies as well as theoretical calculations suggest that the encapsulated CuPc molecule was distorted in zeolite-Y with keeping of the square-planar symmetry around the center copper (II) ion. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cplett.2005.08.140

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Electron paramagnetic resonance (EPR) spectra of partially copper ion exchanged Na-Y zeolite (CuNa-FAU) were measured in the presence of paramagnetic gases such as nitrogen monoxide (NO) and oxygen (O-2) as a function of temperature (110-270 K). The EPR signal intensities of the Cu2+ ions deviated from those predicted by Curie's paramagnetic law due to the magnetic interaction between the Cu2+ ions and paramagnetic gaseous molecules adsorbed on the zeolites; the minimum signal intensity was observed at 150-170 K for CuNa-FAU with NO and the maximum intensity was observed at 170-190 K for CuNa-FAU with O-2. The temperature dependent signal intensities, accompanying the NO adsorption, were discussed in terms of the Langmuir adsorption model in the higher temperature range of 150-190 K. (c) 2005 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.micromeso.2005.04.011

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

An electron paramagnetic resonance (EPR) study was carried out for O-2 molecule adducts formed on cobalt-phthalocyanine encapsulated into Y-type zeolite (CoPc-in-Y). The EPR spectrum, which is characteristic of a superoxide-type O-2-adduct to CoPc-in-Y, was observed when O-2 molecule was introduced into CoPc-in-Y with either ammonia (NH3) or n-butylamine (n-BuNH2) as an axial ligand. The number of the O-2-adduct was found to strongly depend on measurement temperature as well as on the axial ligand employed. The maximum spin concentration of (O-2-CO)Pc2+(n-BuNH2)-in-Y was about one order of magnitude higher than that of (O-2-CO)Pc2+(NH3)-in-Y. The results are discussed in terms of the size of the axial ligands and of the magnetic interaction of the O-2-adduct with paramagnetic O-2 adsorbed on zeolite. (c) 2004 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.micromeso.2004.11.017

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The cathodic polarization of strontium-doped lanthanum ferrite, La1-xSrxFeO3-alpha, was studied in the hydrogen-oxygen fuel cell using proton-conducting SrCe0.95Yb0.05O3-alpha as an electrolyte. The overpotential of La0.7Sr0.3FeO3-alpha cathode was smaller than those of other perovskite-type oxides such as La0.7Sr0.3MnO3-alpha and La0.7Sr0.3CoO3-alpha, and platinum at 773-973 K. The best cathodic performance was obtained for La0.7Sr0.3FeO3-alpha heat-treated at 1173 K. The cathode resistance of La0.7Sr0.3FeO3-alpha was independent of pO(2) while that of sputtered platinum was proportional to pO(2)(-1/4). (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2004.08.008

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The nitration of alkanes by using nitric acid as a nitrating agent in acetic acid was efficiently promoted by vanadium-substituted Keggin-type phosphomolybdates such as [H4PVMo11O40], [H5PV2Mo10O40], and [H6PV3Mo9O40] as catalyst precursors. A variety of alkanes including alkylbenzenes were nitrated to the corresponding nitroalkanes as major products in moderate yields with formation of oxygenated products under mild reaction conditions. The carbon-carbon bond cleavage reactions hardly proceeded. ESR, NMR, and IR spectroscopic data show that the vanadium-substituted polyoxometalate, for example, [H4PVMo11O40], decomposes to form free vanadium species and [PMo12O40](3-) Keggin anion. The reaction mechanism involving a radical-chain path is proposed. The polyoxometalates initially abstract the hydrogen of the alkane to form the alkyl radical and the reduced polyoxometalates. The reduced polyoxometalates subsequently react with nitric acid to produce the oxidized form and nitrogen dioxide. This step would be promoted mainly by the phosphomolybdates, [PMo12O40](n-), and the vanadium cations efficiently enhance the activity. The nitrogen dioxide promotes the further formation of nitrogen dioxide and an alkyl radical. The alkyl radical is trapped by nitrogen dioxide to form the corresponding nitroalkane.

DOI： 10.1002/chem.200400049

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

2,2'-Bi[-3(2H)-thioplienon]ylidene with two bicyclo[2.2.2]-octadiene moieties was quantitatively converted to thioindigo by the retro-Diels-Alder reaction. The thioindigo solid obtained from the precursor had the P2(1)/c structure which was different from the commercial thioindigo samples (P2(1)/n). (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2004.10.028

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

CW-EPR studies of NO adsorbed on sodium ion-exchanged zeolites were focused on the geometrical structure of NO monoradical and (NO)(2) biradical formed on zeolites. The EPR spectrum of NO monoradical adsorbed on zeolite can be characterized by the three different g-tensor components and the resolved y-component hyperfine coupling with the N-14 nucleus. Among the g-tensor components, the value of g,, is very sensitive to the local environment of zeolite and becomes a measure of the electrostatic field in zeolite. The temperature dependence of the g-tensor demonstrated the presence of two states of the Na-NO adduct, in rigid and rotational states. The EPR spectra of NO adsorbed on alkaline metal ion-exchanged zeolite and their temperature dependency are essentially the same as that on sodium ion-exchanged zeolite. On the other hand, for NO adsorbed on copper ion-exchanged zeolite it is known that the magnetic interaction between NO molecule and paramagnetic copper ion are observable in the spectra recorded at low temperature. The signals assigned to (NO)(2) biradical were detected for EPR spectrum of NO adsorbed on Na-LTA. CW-EPR spectra as well as their theoretical calculation suggested that the two NO molecules are aligned along their N-O bond axes. A new procedure for automatical EPR simulation is described which makes it possible to analyze EPR spectrum easily. In the last part of this paper, some instances when other nitrogen oxides were used as a probe molecule to characterize the zeolite structure, chemical properties of zeolites, and dynamics of small molecules were described on the basis of selected literature data reported recently. (C) 2003 Published by Elsevier B.V.

DOI： 10.1016/j.saa.2003.10.045

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Language：English   Publisher：Ehime University  

Continuous wave (CW)-electron paramagnetic resonance (EPR) studies of NO adsorbed on sodium ion-and other ion-exchanged zeolites are reviewed. The EPR spectrum of NO monoradical adsorbed on zeolite can be characterized by the three different g-tensor components and the resolved y-component hyperfine coupling with the ^<14>N nucleus. Among the g-tensor components, the value of g_<zz> is very sensitive to the local environment of zeolite and becomes a measure of the electrostatic field in zeolite. The EPR spectra of NO adsorbed on alkaline metal ion-exchanged zeolite are essentially the same as those on sodium ion-exchanged zeolite. The signals assigned to (NO)_2 biradical were detected for EPR spectrum of NO adsorbed on Na-LTA. CW-EPR spectra as well as their theoretical calculation suggested that the two NO molecules are aligned along their N-O bond axes.

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Other Link： http://iyokan.lib.ehime-u.ac.jp/dspace/handle/iyokan/1411

Language：Japanese   Publisher：Japanese Society for Engineering Education  

The basic scientific and technological knowledge and experience that incoming students of our university possess have been inspected. It was clearly shown that such knowledge was based not on experience but on desk work. Usually students had not had the opportunity to obtain such knowledge in actual situations, and many students lost interest in studying engineering. In order to improve this situation and produce creativity in students, we developed a laboratory course to provide fundamental scientific and technical experience to our freshmen. This academic year(2002), over 340 students belong to four different departments will take this new course. The preliminary outcomes will be reported.

DOI： 10.4307/jsee.51.2_31

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The conductivities of zeolite/poly(tetrafluoroethylene) composite membranes were measured in the presence of water vapor at 75-150degreesC. The conductivity of composite membranes depended on zeolite structure, zeolite content, and exchangeable cation in zeolite; the Li ion-exchanged Y-type zeolite/poly(tetrafluoroethylene) composite membrane with 80 wt.% of zeolite powder showed the highest conductivity among the composite membranes tested in the present study. It was found that the conductivity increased with an increase in the amount of water adsorbed on the composite membrane.

DOI： 10.1039/b207807d

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Nitrogen monoxide (NO) introduced into partially and fully lithium ion (Li+)-exchanged A-type zeolite was studied by X-band EPR measurements. Two types of NO species, NO monoradical and NO-NO biradical, were detected for the partially ion-exchanged zeolite, while the latter was less detectable for the fully ion-exchanged one. The EPR parameters of the NO monoradical provided evidence that the electrostatic field associated with Li+ ions in A-type zeolites is weaker than that with Na+ ions. It was found that the molecular distance of NO biradical formed in partially Li+-exchanged zeolite was shorter than that in sodium ion-exchanged A-type zeolite.

DOI： 10.1039/b203930c

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Language：Japanese   Publisher：化学工業社  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

CdS clusters encapsulated in Y-type zeolite were prepared by a novel technique with non-aqueous systems. The mechanical mixture of CdCl(2).2.5H(2)O crystal with Y-type zeolite was heated at 773 K, followed by the H(2)S treatment at 373 K, resulting in the formation of CdS clusters with the size &lt;2.3 nm.

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Copper ion-exchanged zeolites have widely been studied as the catalysts for NOx emission control. Cu-MFI zeolites, especially over-exchanged Cu-MFI, are very active for the catalytic decomposition of NO. The reaction mechanisms and the active sites suggested are summarized. The newly developed selective catalytic reduction of NO with hydrocarbons in the presence of excess oxygen is then introduced. The role of oxygen and the deactivation of the zeolite catalysts are discussed. In the last chapter, the high ability of Cu-zeolites for NO adsorption is overviewed. Here, some fundamental aspects of the bonding and the molecular diffusion of NO or NO2 Molecules in zeolites are also summarized. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0926-860X(01)00823-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Nitrogen monoxide (NO) introduced into sodium ion-exchanged A-type (Na-A) zeolite was studied by temperature- and NO pressure-dependent EPR measurements at Q-band in the temperature range between 5 and 140 K. The experimental spectra were successfully utilized to determine accurate values of the g and A(N-14) tensors of NO monoradical and the g tensors and zero field splitting (ZFS) parameters, D and E, of the NO-NO biradical. Two different EPR spectra corresponding to low and high temperature forms of the NO monoradical were observed when the NO pressure was low (P-NO less than or equal to 3.1 kPa). Based on the g and A tensors, the former was attributed to a rigid form and the latter to a rotational form of the monoradical. For higher NO pressure, the biradical became dominant. The structure of the biradical was discussed in terms of the D and g tensors combined with the spectral line shape simulation method.

DOI： 10.1021/jp0009709

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Temperature-dependent EPR spectra of nitrogen monoxide (NO) introduced into sodium ion-exchanged A-type (Na-A) zeolite demonstrated that two types of NO monoradical and one NO-NO radical pair were formed on the zeolites and that the thermally less stable NO monoradical was converted into the thermally stable one upon warming from 30 K to 100 K.

DOI： 10.1246/cl.2000.736

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

A broad-line H-1-NMR study was carried out; to examine the local structure of poly(methylmethacrylate) (PMMA) grafted onto Poly(tetrafluoroethylene) (PTFE). The NMR spectra were observed for three different samples with 1.0, 5.4, and 7.0 wt % PMMA over the temperature range from 150 to 380 K. With the help of selectively deuterated PMMA (PMMA-d(5) and PMMA-d(8))-grafted samples, the NMR spectra were analyzed in terms of two components-a Gaussian (G) component, and a Lorentzian (L) component. Based on the second moments ([Delta H-2]) analysis, the L and G components were attributed to the H-1-H-1 dipolar interactions within one CH3 group and the interactions of CH, groups that are closely located in aggregated PMMA chains. Combining the results with the temperature dependence of [Delta H-2] and the angular resolved XPS, the location and rotational motion of PMMA grafted onto PTFE are discussed. (C) 1999 John Wiley & Sons, Inc.

DOI： 10.1002/(SICI)1097-4628(19991107)74:6<1386::AID-APP10>3.0.CO;2-Z

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS INC  

An ESR and F-19-NMR study was carried out to elucidate the reduction kinetics of PTFE with aromatic radical anions (anthracene, benzophenone, biphenyl, and naphthalene), whose counter cation is Na+, in THF solvent. The ESR signal intensities of aromatic radical anions decayed according to the second-order equation whose rate depends on the kind of radical anions; the relative order being naphthalene (1.00) much greater than biphenyl (0.03) &gt; anthracene (0.02) &gt; benzophenone (0.003). The defluorination from PTFE was examined by a high-resolution F-19-NMR method of NaF disolved in an ethanol/water mixed solvent. When an excess amount of Na metal was present, the yield of NaF exceeded the initial concentration of aromatics. The result suggests that the aromatic radical anions are regenerated by the reaction with excess Na metal. The amounts of NaF salts produced during the reducing process were also followed by the same order as the decaying rates of aromatic radical anions. (C) 1999 John Wiley & Sons, Inc.

DOI： 10.1002/(SICI)1097-4628(19991010)74:2<286::AID-APP8>3.0.CO;2-S

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC  

A SiO2-pillared manganese titanate (SiO2-MTO) with layered structure, which has a surface area as large as more than 700 m(2)/g, effectively catalyzed the NH3 oxidation with high selectivity to N-2, The H-2 temperature-programmed reduction results suggested that the manganese ions in SiO2-MTO were in an oxidation state of +3 even in the absence of either Rb+ or C10H21NH3+ ions as a charge-balancing cation, The observed high selectivity to N-2 is attributable to oxygen vacancies associated with Mn3+ ions in the layer. (C) 1999 Academic Press.

DOI： 10.1006/jcat.1999.2615

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Electron spin resonance (ESR) spectroscopy was used to study the effect of zeolite structure on the motional dynamics of NO2 adsorbed on the zeolites. The temperature-dependent ESR spectral line shapes were quantitatively analyzed using the slow-motion ESR theory. It was observed that the motional dynamics of NO2 is strongly dependent on the structure of the zeolite (Beta-type, ZSM-5, mordenite, L-type and ferrierite zeolites). The following important observations were made. (1) In zeolites with similar channel structures, the diffusion rate of NO2 is proportional to the channel size, and the order of the diffusion rates is Beta-type &gt; ZSM-5 &gt; ferrierite and L-type &gt; mordenite. (2) The diffusion of NO2 is faster in the zeolites with multi-dimensional channels (Beta-type, ZSM-5 and ferrierite) than that in those with uni-dimensional channels (L-type and mordenite). (C) 1999 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S1387-1811(99)00038-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The effect of poly(tetrafluoroethylene) (PTFE) crystallinity on the graft polymerization of methylmethacrylate (MMA) was examined using ESR, XPS, and thermogravimetry (TG) methods. The MMA monomers were graft polymerized by the initiation of radicals generated in PTFE by the ionization radiation. The number of PTFE radicals reacted with MMA was measured by ESR. Combining the ESR results with the amounts and depth profile of grafted PMMA, the graft polymerization was found to effectively proceed in the amorphous region for the lower crystalline PTFE. For the highly crystalline PTFE, the polymerization on the surface of the crystallites becomes relatively important. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0969-806X(99)00292-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The diffusion and bonding of NOx (x = 1, 2) and Cu2+ species in zeolites are reviewed, based mainly on our own research. The molecular motion of adsorbed NO2 has been examined with EPR in several zeolite samples and analyzed using the slow-motional EPR theory. In X- and Y-type zeolites the broadening of the spectra with temperature could be analyzed by simulations using a rotational diffusion model in agreement with earlier results in Vycor glass and Cu-metal. For the diffusion of NO2 in Na-mordenite and Na-ZSM-5 the broadening of the spectra with increased temperature could be better simulated with the Heisenberg type of spin exchange model. The exchange was attributed to the interaction between NO2 molecules diffusing along the zeolite channels. In Na-ZSM-5 the spin exchange rate increased rapidly with an increasing Si/Al ratio of the zeolite. The effect was attributed to the hindrance against diffusion by Na+, the amount of which increases with a decreased Si/Al ratio. The rates increased with increasing number of H2O molecules adsorbed on the zeolite because of weaker interaction between NO2 and the surface. A more detailed slow-motional analysis indicated that at each temperature a distribution of diffusion rates occurs. NO adsorbed on Na-A zeolite was found to be present as monomer at low pressure (&lt; 1 mbar) while a dimer characterised by a triplet state ESR spectrum involving Delta M-s = 1 and Delta M-s = 2 features became dominant at higher NO pressure (&gt; 100 mbar). The triplet was absent in calcium ion-exchanged A-type zeolite indicating that the NO-NO species depends on Na+ for its stability. The detailed structure of a Cu2+ complex with water molecules in Cu-ZSM-5 zeolite was characterised with ENDOR at 4 K. The complex has an axial distorted octahedral structure with two water molecules at a longer distance in axial position and four molecules in the equatorial positions. The Cu2+ complexes with ammonia and deuterated ammonia have been investigated with electron nuclear double resonance (ENDOR). Simulations of the ENDOR spectra with H-1, H-2 and N-14 hyperfine interactions have been undertaken. The analysis indicates that the complex has a square planar structure with four ammonia ligands.

DOI： 10.1039/a809284b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The adsorption properties of nitrogen monoxide (NO) on various silver ion-exchanged zeolites were examined by adsorption-desorption measurements in a fixed bed flow apparatus. Both reversible (q(rev)) and irreversible (q(irr)) adsorption of NO is dependent on the aluminum content in the zeolites and the zeolite structure. The amounts of reversible and irreversible adsorption of NO per silver ion increased with decreasing aluminum content of the zeolites and were constant, independent of the ion exchange level for ZSM-5 zeolites, but increased with the ion exchange level for mordenite zeolites (MOR). It was also found that the adsorption properties are dependent on the temperature and pressure of adsorption: q(irr) and q(rev) of Ag-MOR increased with decreasing adsorption temperature and increasing adsorption pressure. Furthermore, the influence of preadsorbed gases on the Ag-MOR zeolite was investigated, and an enhancement of q(rev) was observed when NO2 was preadsorbed. The NO species adsorbed on the Ag-MOR zeolite were characterized by infrared (IR). Most of the reversibly adsorbed NO species are NOdelta+ and some N2O adsorbed on Ag+, and the irreversibly adsorbed NO species are some N2O, NOdelta+, and a small amount of NOdelta-, NO2delta+.

DOI： 10.1021/cm9803962

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A novel three-dimensional information imaging, spin exchange rate (SER) spectra, was proposed to use for the analysis of complicated molecular motions of gaseous molecules in powder solids. It has successfully been applied to characterize molecular dynamics of NO2 on Na-mordenite. This spectrum directly illustrates the detailed dynamic information of motion of NO2 versus temperature, which showed that (1) the molecular motion of NO2 is a superposition of individual motions, corresponding to different spin exchange rates; (2) for a given temperature, there is a dominant spin exchange rate and the rate increases with increasing temperature; (3) the distribution of active spin exchange rates is broadened with increasing temperature and then decreases again at higher temperature; and (4) there are two different dynamical processes in the temperature range 110-260 K: one with an activation energy of 486 J/mol is attributed to adsorption; the other with 4390J/mol is a desorption process, and they reach adsorption-desorption equilibrium. Theoretical interpretations of these observations are also given in this paper.

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Language：Chinese   Publishing type：Research paper (scientific journal)   Publisher：HIGHER EDUCATION PRESS  

The relations of the adsorption properties and the behavior of catalytic decomposition of nitrogen monooxide over various copper ion-exchanged zeolites were studied by the means of in situ FTIR and temperature-programmed desorption (TPD), The results demonstrated that NO+, O--Cu-NO and NOB species were formed on the surface of the zeolites and desorbed at 350 similar to 400 K(denoted as alpha), 400 similar to 480 K (beta) and 650 similar to 700 K (gamma), respectively. It was found that the kinds and the amounts of the species were greatly changed with the zeolite structure and the copper ion exchange level, i. e. Cu-MFI, Cu-MOR and Cu-OFF/ ERI gave alpha, beta and gamma peaks; Cu-FER gave alpha and beta peaks; Cu-LTL and Cu-FAU only gave a peak. The amounts of desorption were increased linearly;with the exchange level of copper on Cu-MFI. The O-2 desorption peak appeared at the same temperature as that of the gamma peak. In addition, by comparing the present; results with the behavior of catalytic decomposition of NO, it is also found that NO3- species play a key role in the catalytic decomposition of NO and the formation of O-2 over the zeolites.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

An EPR study has been performed on a low Ag+-exchanged Na-A zeolite (Ag0.1Na11.9-A) on which ammonia had been adsorbed followed by exposure to gamma-radiation at 77 K. The formation of Ag atoms, normally observed for zeolites with a high Ag content, is abated by the presence of ammonia. New EPR spectra with the silver hyperfine coupling constant slightly smaller than that of isolated silver atoms were observed. The new spectra were assigned to two silver-ammonia complexes, [Ag-NH3](0) and [Ag-(NH3)(2)](0), the former being more thermally stable than the latter; the latter decayed at 150 K. The EPR parameters of [Ag-NH3](0) were determined as follows: g(iso) = 2.005 and a(iso)(Ag-107) = 38.0, A(perpendicular to)(N-14) = 1.4, A(parallel to)(N-14) = 1.7 and a(iso)(H-1) approximate to 0 mT. The formation reactions and possible locations of the adduct radical are discussed in terms of annealing temperatures and the amount of ammonia introduced.

DOI： 10.1039/a707157d

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The catalytic activity for the oxidation of isobutane catalyzed by 12-molybdophosphoric acid was much changed by the V(5+)- and Cs(+)-substitution for Mo(6+) and H(+), respectively. The best yield of methacrylic acid was 9.0% and was obtained for the heteropoly catalyst with V and Ca contents of 1 and 2.5, respectively. The high catalytic activity obtained for Cs(2.5)Ni(0.08)H(1.34)PVMo(11)O(40) is presumably due to the high surface area. The activities of 12-molybdovanadophosphoric acids as well as those of 12-molybdophosphoric acid partially salified with Csf were controlled by the oxidizing ability of catalysts. The conversion vs selectivity relationships, the simulation of the data, and kinetic results for Cs(2.5)Ni(0.08)H(1.34)PVMo(11)O(40) and Cs(2.5)Ni(0.08)H(0.34)PMo(12)O(40) catalysts show that the first steps, i.e., selective and complete oxidation reactions of isobutane, are rate-determining and mainly catalyzed by molybdenum ion and that vanadium ion efficiently accelerates the selective oxidation of methacrolein to methacrylic acid. Cs(+)-substitution for H(+) in H(3.84)Ni(0.08)PVMo(11)O(40) greatly change the selectivity up to a Cs content of 2.5 and suppressed the elimination of the vanadium ion from the Keggin anion.

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DOI： 10.1021/jp980616z

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Language：Japanese   Publisher：ゼオライト学会  

DOI： 10.20731/zeoraito.15.3.104

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DOI： 10.1021/jp972677n

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Language：Chinese   Publishing type：Research paper (scientific journal)   Publisher：HIGHER EDUCATION PRESS  

The adsorption properties of nitrogen monooxide (NO) on various metal ion-exchanged zeolites were examined by adsorption-desorption measurement in a fixed bed flow apparatus. The amounts of reversible (q(rev)) and irreversible (q(irr)) adsorption of NO were changed with the types of metal ion and zeolite structure. Among the samples tested, the copper ion-exchanged ZSM-5 and silver ion-exchanged mordenite showed the greatest ability for reversible adsorption of NO. The amounts of reversible and irreversible adsorption of NO per metal ion exchanged increased with decreasing aluminum content of zeolites, and were constant, independent of the ion exchange level for ZSM-5 zeolites, but changed with the ion exchange level for mordenite zeolites. It has also been found that the adsorption properties are dependent on adsorption temperature: q(irr) increased with decreasing adsorption temperature for both copper and silver ion exchanged zeolites, however, q(rev) of Cu-ZSM-5 showed a maximum at 243 K, and q(rev) of Ag-MOR increased with decreasing adsorption temperature.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The reduction-oxidation of copper ions in Cu-Pd-H3PO4/SiO2 catalysts, active in the direct oxidation of benzene to phenol, was studied by means of electron spin resonance spectroscopy. The isolated and aggregated copper (II) ions were found to exist on the Cu-Pd-H3PO4/SiO2 catalyst after evacuation at room temperature. A portion of the Cu(II) ions supported on SiO2, isolated Cu(II) ions coordinated with PO43-, was found to be reversible with alternate reduction-oxidation treatments at 200 degrees C. When the ESR results were compared with the formation rates of phenol, the 'reversible' Cu(II) ions were concluded to be responsible for catalytically active sites. (C) 1997 Elsevier Science B.V.

DOI： 10.1016/S0926-860X(97)00228-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Electron spin resonance (ESR) was used to study the motional dynamics of NO2 adsorbed on Na-ZSM-5 with different SiO2/Al2O3 ratios at 3-160 K. The temperature dependence of the ESR spectral lineshape was quantitatively analyzed with slow-motion ESR theory. The computer analysis with the Heisenberg spin exchange model reveals that the spin exchange rate of NO2 below 160 K increases quickly as the SiO2/Al2O3 ratio is increased from 23.8 to 70 and to 200. IL is concluded that the difference in the amount of Na+ among the various zeolites is the main reason for the observed variation in spin exchange rates.

DOI： 10.1016/S0009-2614(97)00417-X

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Language：English   Publisher：HIGHER EDUCATION PRESS  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The temperature dependent ESR spectra of NO2 adsorbed on Na-mordenite have been studied in the temperature range 77-300 K. An analysis based on slow-motional ESR theory shows that the reversible change with temperature is caused by Heisenberg spin exchange. The activation energy is 0.8-1.6 kcal/mol depending on NO2 concentration. The spin exchange is probably caused by the interaction of NO2 molecules with each other as they diffuse along the channels of Na-mordenite.

DOI： 10.1016/0009-2614(96)00416-2

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Language：Japanese   Publisher：化学同人  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：SOC CHEMICAL ENG JAPAN  

Liquid phase oxidation of benzene to phenol was studied using palladium/silica catalysts prepared by impregnation and ion-exchange methods. The catalyst prepared by impregnation showed high catalytic activity, but the catalyst prepared by ion-exchange showed no catalyst activity. The high catalytic performance of the former was ascribed to the presence of Cl--. ions on the catalyst surface. The reaction of benzene with hydrogen peroxide revealed that hydroxyl radical produced by the decomposition of hydrogen peroxide was an intermediate in the oxidation of benzene, and that Cl- ion suppressed a side reaction between hydrogen peroxide and hydrogen supplied on the catalyst.

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An ESR study was carried out for sodium-containing silicon clathrate compounds, NaxSi136 with 3 less than or equal to x less than or equal to 10. For Na3Si136 a quartet with an isotropic hf splitting of 13.3 mT was observed together with the weak septet of 6.7 mT at 4 K; the former and the latter being attributed to the Na atom and the dimer cation Na-2(+) respectively. The temperature-dependent ESR spectral intensity of the Na atom was observed over a wide temperature range from 4 to 200 K. A deviation from the paramagnetic Curie law was observed in the higher temperature region and is discussed in terms of a thermal electron excitation from the Na impurity level to the conduction band of the silicon clathrate compound.

DOI： 10.1016/0009-2614(95)01110-U

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Various noble metal ion-exchanged MFI zeolites have been examined as catalysts for the selective reduction of NO by ethene in the presence of excess oxygen. Of the catalysts ion-exchanged for Ru, Rh, Pd, Ir, and Pt, Pt-MFI zeolite showed the highest catalytic activity for the conversion of NO into N-2. The catalytic activity was not reduced upon the addition of 8.6 vol.-% water vapor or 300 ppm sulfur dioxide in the reactant stream. It was hardly changed during the continuous experiment of 1000 h except for the initial period of use, indicating the high durability of Pt-MFI. Temperature-programmed decomposition and dynamic XRD measurements over Pt-MFI revealed that metallic platinum particles were formed through the decomposition of tetraammineplatinum ion during the pre-treatment around 673 K in helium atmosphere. The sizes of platinum particles were confirmed by TEM to be about 3 and 13 nm and did not change after use in the catalytic run.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Two radicals, hydrogen addition-type radicals (CF2H-CF2 .), and propagating radical of polytetrafluoroethylene (R-CF2-C-2 .), were generated by gamma-irradiation of tetrafluoroethylene adsorbed on zeolites. The formation mechanisms for two radicals are discussed based on the ESR results.

DOI： 10.1246/cl.1995.601

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The adsorbability of nitrogen monoxide (NO) on cobalt ion-exchanged zeolites has been studied by pressure swing adsorption (PSA), temperature-programmed desorption (TPD) and IR techniques on the following zeolite samples; ZSM-5, mordenite, ferrierite, offretite/erionite, L-, Y- and X-type. The amounts of NO reversibly (q(rev)*) and irreversibly (q(irr)*) adsorbed at 273 K per cobalt ion exchanged, increased with decreasing aluminium content of the parent zeolite. On Go-ZSM-5 zeolite, both q(rev)* and q(irr)* were constant, independent of the ion exchange level. Over the range 273-523 K the maximum amount of reversible adsorption on Go-ZSM-5 or Co-mordenite has been observed at around 323-473 K, while the amount of irreversible adsorption decreased monotonically with increasing adsorption temperature. It has been confirmed on Go-ZSM-5 that most of the reversible adsorbates at 298 K are NO2+. The irreversibly adsorbed NO species on Co-ZSM-5 have been attributed to two kinds of dinitrosyl adsorbates. One has an ON-Co-NO bond angle of 99 degrees and desorbs around 390 K, while the bond angle of the other is 123 degrees and the desorption temperature is ca. 510 K. On mordenite and Y-type zeolites only the latter species was observed.

DOI： 10.1039/ft9959100767

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Phenol is readily produced by some stoichiometric reactions of benzene with certain copper(II) salts. The main part of the reaction using copper(II) sulfate is estimated to be expressed by the following equation:
Benzene + 2CuSO(4) + H2O = Phenol + Cu2SO4 + H2SO4.
This reaction was carried out in a flow system at 300 degrees C, where a vapor mixture of benzene and water flowed through a packed bed of copper(II) sulfate supported on silica gel. The products were mainly phenol and CO2 with a trace amount of biphenyl. The phenol yield became appreciable at temperatures higher than 250 degrees C, and reached a maximum at ca. 300 degrees C. At higher temperatures, the CO2 yield increased along with the consumption of phenol. The percentage yield of phenol based on copper(II) salt was 86% at the highest. Although copper(II) phosphate was similarly useful, it required a higher reaction temperature (ca. 500 degrees C).

DOI： 10.1246/bcsj.68.1747

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Language：Japanese   Publisher：広信社  

CiNii Books

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Language：English   Publishing type：Research paper (scientific journal)  

Liquid phase oxidation of benzene to phenol was studied using palladium/silica catalysts prepared by impregnation and ion-exchange methods. The catalyst prepared by impregnation showed high catalytic activity, but the catalyst prepared by ion-exchange showed no catalyst activity. The high catalytic performance of the former was ascribed to the presence of Cl-ions on the catalyst surface. The reaction of benzene with hydrogen peroxide revealed that hydroxyl radical produced by the decomposition of hydrogen peroxide was an intermediate in the oxidation of benzene, and that Cl-ion suppressed a side reaction between hydrogen peroxide and hydrogen supplied on the catalyst. © 1995, The Society of Chemical Engineers, Japan. All rights reserved.

DOI： 10.1252/kakoronbunshu.21.997

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE PUBL B V  

ESR spectra of NO2 adsorbed on X-and Y-type zeolites were observed in the temperature range 77-346 K Based upon spectral simulation using a Brownian diffusion model, motional dynamics of NO2 adsorbed on zeolite surface were analyzed quantitatively. In the case of X-type zeolite, it was found that the ESR spectra below 100 K is near the rigid limit. Above 230 K, the average rotational correlation time decreased from 1.7 x 10(-9) (230 K) to 7.5 x 10(-10) sec (325 K) with increasing temperature and its degree of anisotropy was very close to one (N = 1.25). On the other hand, the temperature-dependent ESR spectra of NO2 adsorbed on Y-type zeolite were observed to be somewhat different from that for X-type zeolite.

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Language：English   Publisher：ELSEVIER SCIENCE BV  

DOI： 10.1016/0920-5861(94)80089-8

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Selective catalytic reduction of nitrogen monoxide (NO) by hydrocarbon in an oxidizing atmosphere has been studied over platinum-MFI zeolite (Pt-MFI) in synthesized or actual diesel engine exhaust gases. The activity of Pt-MFI in the synthesized gas, containing 10% water, changed in the early stage of the use, leveled off after 150-200 h, and remained constant for more than 800 h. The Pt-MFI catalyst also showed stable activity at 423-773 K and 10 000-150 000 h(-1) (gas hourly space velocity) in actual engine exhaust with light oil as a fuel. The degree of nitrogen monoxide reduction increased linearly upon addition of ethylene into the exhaust gas.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE PUBL B V  

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE PUBL B V  

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Breakthrough curves of NO adsorption on various metal ion-exchanged zeolites have been employed to evaluate the intraparticle effective diffusion coefficient (Dj). D{ was 0.7 x 10-3—29 x 10-3 cm2-s_1 and was changed with zeolite structures, metal ions exchanged, and adsorption temperature. On MFI zeolite, D{ was dependent on the radius of metal ion, and a maximum D{ was observed around 0.09 nm of the radius. With Cu-ZSM-5 and Agmordenite, the maximum Dx was observed around 250 K, while the Dj of Comordenite was not varied with the adsorption temperature. © 1994, The Chemical Society of Japan. All rights reserved.

DOI： 10.1246/nikkashi.1994.748

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The adsorption properties of nitrogen monoxide (NO) on various metal ion-exchanged zeolites were examined by adsorption-desorption measurements in a fixed bed flow adsorption apparatus. Among the samples used, the copper ion-exchanged ZSM-5 zeolites showed the greatest ability for reversible adsorption of NO; therefore, it has been studied in more detail. The amounts of reversible and irreversible adsorption of NO per copper ion exchanged increased with decreasing aluminum content of the zeolite, and were constant, independent of the ion exchange level. The NO species adsorbed on the zeolite were characterized by infrared (IR) and temperature-programmed desorption (TPD) techniques. Most of the NO reversibly adsorbed is the NO+ adsorbed on Cu2+, and the NO irreversibly adsorbed is the residual of NO+, nitrate (NO3-), nitrite (NO2-), and NO2+. The irreversibly adsorbed species gave the desorption peaks at 400, 463, and 663 K. The total amount of NO desorbed in the TPD experiment is in good agreement with the amount of irreversible adsorption of NO evaluated from the adsorption-desorption measurement.

DOI： 10.1021/la00033a015

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHAPMAN HALL LTD  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Proton-exchanged ultrastable Y-type zeolite showed good activity for the novel catalytic reaction to form directly ethyl methyl ketone or acetone from 1-butene or propene and water. The formation rates of these ketones were higher than those on MoO3-based catalysts in the oxidation of 1-butene and propene by oxygen. On the basis of product distribution and solid state Al-27 MASNMR, the direct formation of ketones from olefins and water in the absence of oxygen is suggested to be a two-step reaction through corresponding alcohols, in which a strong acidic site on extra-framework Al species may be responsible for the dehydrogenation of intermediate alcohols. Among the extra-framework Al ions with the coordination numbers of 4, 5, or 6, the penta-coordinated Al ions are provisionally attributed to the strong acid sites.

DOI： 10.1016/0304-5102(93)85080-D

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Language：Japanese   Publisher：化学同人  

CiNii Books

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE PUBL B V  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

In the presence of O2, SO2, and H2O selective reduction of NO by hydrocarbon over various catalysts, especially, over copper ion-exchanged zeolite has been studied. Simultaneous presence of O2 and hydrocarbon such as ethene, propene, and propane with NO in the reactant gas resulted in the great enhancement of the catalytic activity for the removal of NO at low temperature (473-673 K). On the other hand, the addition of CO, H-2, or CH4 to the NO+O2 system did not cause any selective reduction of NO. In the former selective reduction, the increment of concentration of hydrocarbon increased the conversion into N2 and expanded the active temperature region. Addition of oxygen to reactant stream is necessary to achieve the selective reduction of NO, and with Cu-MFI zeolite the maximum activity was observed in the range of oxygen concentration of 0.8-2.0%. No deterioration in the catalytic activity was observed at 573 K even after 30 h of continuous service. When SO2 or H2O was added to NO+O2+hydrocarbon gas stream, a certain decrement in the catalytic activity of Cu-MFI zeolites was observed. Within the present experiments, the activity was restored in its absence. Various metal ion-exchanged zeolites, metal loading alumina, and oxides have been screened as catalysts for the reaction and it was clarified that Cu-MFI zeolite catalysts are the most active at high SV region. The addition of copper to zeolites, alumina, and silica-alumina greatly enhanced the activities.

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Platinum ion-exchanged ZSM-5 zeolite efficiently reduced nitrogen monoxide to nitrogen by ethene in an oxidizing atmosphere below 500 K and the catalytic activity was not affected by the presence of 8.6 vol% water vapor.

DOI： 10.1246/cl.1992.2235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Infrared spectroscopy combined with an isotropic tracer method has been used to study the adsorption of NO over copper ion-exchanged ZSM-5 zeolites and to elucidate the reaction mechanism of catalytic decomposition of NO. Three distinct states of adsorbed NO have been detected, being attributed to NO(delta+), NO(delta-), and (NO)2delta-. The intensities of 1827- and 1734-cm-1 bands, symmetric and asymmetric stretching vibration of the dimer species, respectively, concluded that the bond angle ON-Cu-NO in (NO)2delta- is 103-degrees. The IR experiments on evacuated, oxidized, or CO-preadsorbed copper ion-exchanged ZSM-5 zeolites and ESR or phosphorescence measurements indicated that NO(delta-) and (NO)2delta- are formed on copper(I) ions while NO(delta+) on copper(II) ions. The formation of the anionic species depended on the partial pressure of NO, NO(delta-)(ads) + NO(ps) --&gt; (NO)2delta-(ads). The intensities of the infrared bands attributable to NO(delta-) and (NO)2delta- decreased at ambient temperature with reaction time, while that of NO(delta+) increased. The change of the distribution of products in the gas phase with adsorption time was measured and the formation of N2 and N2O was confirmed even at room temperature on the evacuated sample. It follows that the Cu+ ions are active centers, NO(delta-) and/or (NO)2delta- species are intermediates for the decomposition of NO over copper ion-exchanged ZSM-5 zeolite catalyst, and the catalytic reaction cycle proceeds at or above 573 K, at which oxygen generated through the decomposition can desorb.

DOI： 10.1021/j100202a055

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Among the samples tested, the amounts of reversible and irreversible adsorption of NO were the largest on copper ion-exchanged ZSM-5 zeolite and cobalt ion-exchanged ZSM-5 zeolite, respectively. In the former case, the amounts of reversible and irreversible adsorption of NO were dependent on the aluminum content of zeolite and linearly increased with increasing the exchange level.

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Language：Japanese   Publisher：The Japan Institute of Energy  

DOI： 10.20550/jietaikaiyoushi.1.0_281

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BALTZER SCI PUBL BV  

Among various metal ion-exchanged zeolites, metal loading alumina, and oxides, iron ion-exchanged mordenite was the most active for the selective reduction of nitrogen monoxide to nitrogen by ethene in the presence of oxygen at the temperature as low as 473 K. The catalytic activities of iron ion-exchanged zeolites depended on the zeolite structure and the iron ion exchange level. The effects of the zeolite structure are in the order of MOR &gt; FER &gt; MFI &gt; Y &gt; LTL at 473 K. The activity of iron ion-exchanged mordenite increased with the increment in the exchange level and levelled off above about 60%.

DOI： 10.1007/BF00767201

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The addition of 3.3-3.7 wt% copper resulted in the great increment in the catalytic activity of the parent SiO2-Al2O3 for the title reaction in the wide temperature region 573-900 K.

DOI： 10.1246/cl.1991.1859

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Catalytic decomposition and selective reduction of nitrogen monoxide over copper ion-exchanged zeolite catalysts have been proposed as a new method for removal of NO. The copper ion-exchanged ZSM-5 zeolite (Cu-ZSM-5) was the most active catalyst for NO decomposition. Repeated ion exchange of the ZSM-5 zeolite using aqueous copper(II) acetate solution or addition of ammonia into the aqueous copper(II) nitrate solution brought about the excess loading of copper ions above 100% of exchange level. The activity of the resulting zeolites increased with increasing exchange level and was significantly high even in the presence of oxygen and in the high GHSV region. It was clarified for Cu-ZSM-5 by using IR, ESR, phosphorescence, TPD, and CO adsorption measurements that (1) the Cu2+ ions exchanged into zeolite were reduced to Cu+ and/or Cu+-Cu+ through evacuation at elevated temperature, (2) after exposure to oxygen at 773 K about 40% copper ions in zeolite existed as Cu+ ions, and (3) the NO- adsorbed on Cu+ was an intermediate in the NO decomposition and redox cycle of Cu+ reversible Cu2+ proceeded in the zeolite through the decomposition reaction. The selective reduction of NO by hydrocarbon in the presence of oxygen over Cu-ZSM-5 was remarkably effective for NO removal at low temperature (473-573 K). The rate of Cu-ZSM-5 at 525 K was much higher than those of H-zeolite and alumina catalysts at 673 and 773 K, respectively. The activity for this selective reduction in NO+C3H6+O2 system was not seriously poisoned by the addition of SO2.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Repeated ion exchange of the ZSM-5 zeolite using aqueous copper(II) acetate solution was found to bring about excess loading of copper ions above an exchange level of 100%. The high activity of the resulting catalyst for NO decomposition was consistent for at least 30 h even at short contact time and low NO pressure. The number of copper ions that can absorb NO molecules has been determined by a temperature-programmed desorption technique combined with IR measurement; 94% of Cu2+ ions in ZSM-5 were active for the adsorption. The activity of excessively copper ion exchanged ZSM-5 zeolite was slightly reduced by the oxygen in the feed gas while that of the zeolite, of which the loading amount of copper was less than 100%. was greatly diminished under the same condition. SO2 completely poisons the activity at 673-923 K, but the activity can be regenerated at the higher temperature treatment.

DOI： 10.1021/j100162a053

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Copper ion-exchanged ZSM-5 zeolite is the most active for the selective reduction of nitric oxide by ethene in the presence of oxygen at temperatures as low as 437-573 K among transition metal ion- and proton-exchanged zeolites, and Al2O3. The order of active temperature regions of cation-exchanged ZSM-5 zeolites was Cu (the most active temperature, 523 K) &lt; Co (623 K) &lt; H (673 K) &lt; Ag (723-873 K) &lt; Zn (873 K). The activity of copper ion-exchanged ZSM-5 zeolite did not decrease much even in a high gas hourly space velocity (GHSV) region of more than 10 000 h-1 while those of proton-exchanged zeolites and Al2O3 greatly decreased in such high GHSV regions.

DOI： 10.1016/S0166-9834(00)84146-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The catalytic activity of copper ion-exchanged ZSM-5 zeolites, used for the selective reduction of nitric oxide by propene in the presence of oxygen was only slightly decreased by the addition of sulfur dioxide; for example, the conversion of nitric oxide into nitrogen was changed from ca. 100% in the absence of sulfur dioxide to 85% (773 K) upon the introduction of sulfur dioxide. In contrast, the catalytic activity for nitric oxide decomposition completely disappeared upon addition of sulfur dioxide. These results show that the selective reduction of nitric oxide by hydrocarbon may be practical.

DOI： 10.1016/S0166-9834(00)83286-8

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：KODANSHA LTD  

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：KODANSHA LTD  

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Language：Japanese   Publisher：日本化学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BALTZER SCI PUBL BV  

The catalytic activity of alumina for the title reaction has been found to be greatly improved by the loading of copper. The addition of copper resulted in lowering the active temperature region, the higher maximum activity, and the enhancement of the reaction rate. The maximum effect was observed at 0.3 wt% of the loading amount of copper. A similar enhancement was also confirmed on SiO2-Al2O3.

DOI： 10.1007/BF00769086

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Language：English   Publishing type：Research paper (scientific journal)  

Direct decomposition and selective reduction of nitrogen monoxide over copper ion-exchanged zeolite catalysts are proposed as new methods for removal of NO. The copper ion-exchanged ZSM-5 zeolite (Cu-Z) was the most active catalyst for decomposition of NO. The activity of Cu-Z zeolites increased with increase in the exchange level. The zeolites with copper ion-excange levels of 100% or more, which could be prepared by repeating ion exchange of the ZSM-5 zeolite using aqueous copper(H) acetate solution or addition of ammonia into the aqueous copper(H) nitrate solution, showed significantly high activity even in the presence of oxygen and at high GHSV region. It was clarified concerning Cu-Z, by using IR, ESR, phosphorescence, TPD, and CO adsorption measurements that (1) the Cu2+ ions exchanged into zeolite were reduced to Cu+ and/or Cu+-Cu+ through evacuation at elevated temperature, (2) after exposure to oxygen at 773 K and subsequent evacuation, about 40% copper ions in zeolite existed as Cu+ ions, (3) the NO- species formed by adsorption of NO on Cu+ would be an intermediate in the NO decomposition, and (4) redox cycle of Cu+⇄Cu2+ in the zeolite is probably a key step to achieve the decomposition reaction. Selective reduction of NO by hydrocarbon in the presence of oxygen was first found by the authors and Cu-Z was remarkably effective for NO removal at temperatures as low as 523- 673 K. The activity for this selective reduction in NO+C3H6+O2 system was not poisoned very much by addition of SO2. The conversion into N2 was changed to 85% (773 K) in the presence of SO2, from 100% in the absence of SO2, which is in contrast with the fact that the catalytic activity for direct decomposition NO was completely lost on adding the same amount of SO2. Furthermore, the reduction rate over Cu-Z at 573 K was higher than those over H-zeolite and alumina catalysts at 723 and 773 K, respectively, which have been reported to be active, after findings by the authors. © 1991, The Japan Petroleum Institute. All rights reserved.

DOI： 10.1627/jpi1958.34.375

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Proton exchanged ultrastable Y-type zeolite showed a pronounced catalytic activity for the formation of acetone directly from propene and water. The formation rate of acetone was higher or comparable to those on MoO3-based catalysts in the oxidation of propene by oxygen to produce acetone.

DOI： 10.1246/cl.1990.2289

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1990.1967

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Language：Japanese   Publisher：The Surface Science Society of Japan  

DOI： 10.1380/jsssj.11.110

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

DOI： 10.1016/0167-2738(89)90061-1

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Language：English   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/bcsj.62.583

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1989.213

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Inc.  

The catalytic decomposition of NO has been investigated over various copper ion-exchanged zeolites. At 753 K the Cu2+-exchanged ZSM-5 zeolite with SiO2/Al2O3=23.3 and exchange level=100% showed a high and consistent activity for the reaction even at a contact time of 0.2-0.025 g.sec.cm-3 or GHSV=10000-80000 h-1. The IR, ESR, and TPD experiments made it possible to evaluate the number of Cu2+ ions which could adsorb NO molecules. It follows that the proportion of the copper ions available for NO adsorption is dependent on the zeolite structure, and the activity per cupric ion accessible to NO depends on the Al content of the parent zeolite. © 1988 Elsevier Science Publishers B.V.

DOI： 10.1016/S0167-2991(09)61296-9

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

DOI： 10.1149/1.2096212

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHAPMAN HALL LTD  

DOI： 10.1007/BF01022246

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHAPMAN HALL LTD  

DOI： 10.1007/BF01154008

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Language：English   Publishing type：Research paper (scientific journal)  

Ceria-based oxides with high ionic conductivity were investigated for the solid oxide fuel cell. The ionic conductivity of the ceria-samarium oxide system was higher than that of yttria stabilized zirconia and was the highest among the ceria-based oxides (Fig. 3). The ceria-samarium oxides were used as the electrolytes of oxygen-hydrogen fuel cell. Although the open circuit voltage of the cell for the ceria-samarium oxide system was lower than that for the zirconia-yttria system, the current density for the ceria-samarium oxide system was higher than that for the zirconia-calcia system at low temperatures. The overall overvoltage of the ceria-samarium oxide fuel cell is caused by the resistance and activation overvoltages (Figs. 4 and 5). When the fuel cell is operated at 600'700°C, the output current is largely affected by the electrode material as well as the electrolyte. The perovskite-type oxidei of La0.8Sr0.4CoO3 exhibited a good performance as an oxygen electrode (Fig. 6). The current interruption method revealed that the overvoltage at the oxygen electrode was low for La0&gt
6Sr0.4CoO3 at a small current density, but it was high at a high current density in comparison with Pt electrode (Fig. 5). To suppress the reduction near the hydrogen electrode, a thin film of stàbilized zirconia was coated on the fuel side of a ceria-samarium oxide disk by the ion plating method. The resistance of the fuel cell slightly increased by zirconia coating. However, the fuel cell with zirconia-coated ceria-samarium oxide exhibited a high durability of the cell output and stable open circuit voltage. © 1988, The Chemical Society of Japan. All rights reserved.

DOI： 10.1246/nikkashi.1988.1318

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

DOI： 10.1016/0167-2738(86)90006-8

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Responsible for pages：84-96   Language：Japanese  

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Responsible for pages：951-988  

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Language：Japanese   Publisher：日本芳香族工業会  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：石油学会 ; 1978-  

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Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

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DOI： 10.20731/zeoraito.32.3.80

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Language：Japanese   Publisher：化学工業社  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER CHEMICAL SOC  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Breakthrough curves of NO adsorption on various metal ion-exchanged zeolites have been employed to evaluate the intraparticle effective diffusion coefficient (D(i)). D(i) was 0.7 x 10(-3) - 29 x 10(-3) cm2.s-1 and was changed with zeolite structures, metal ions exchanged, and adsorption temperature. On MFI zeolite, D(i) was dependent on the radius of metal ion, and a maximum D(i) was observed around 0.09 nm of the radius. With Cu-ZSM-5 and Agmordenite, the maximum D(i) was observed around 250 K, while the D(i) of Comordenite was not varied with the adsorption temperature.

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Language：Japanese   Publisher：学会出版センタ-  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：ELECTROCHEMICAL SOC JAPAN  

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Language：Japanese   Publisher：触媒学会  

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