Activation of supported Pd metal catalysts for selective oxidation of hydrogen to hydrogen peroxide
Metadata of CSIR Papers
View Archive Info| Field | Value | |
| Title |
Activation of supported Pd metal catalysts for selective oxidation of hydrogen to hydrogen peroxide
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| Creator |
Choudhary, VR
Gaikwad, AG Sansare, SD |
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| Subject |
Chemistry, Physical
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| Description |
Catalytic activity of supported Pd metal catalysts (Pd metal deposited on carbon, alumina, gallia, ceria or thoria) showing almost no activity in the liquid-phase direct oxidation of H-2 to H2O2 (at 295 K) in acidic medium (0.02 M H2SO4) can be increased drastically by oxidizing them using different oxidizing agents, such as perchloric acid, H2O2, N2O and air. In the case of the Pd/carbon (or alumina) catalyst, perchloric acid was found to be the most effective oxidizing agent. The order of the H-2-to-H2O2 conversion activity for the perchloric-acid-oxidized Pd/carbon (or alumina) and air-oxidized other metal oxide supported Pd catalysts is as follows: Pd/alumina < Pd/carbon < Pd/CeO2 < Pd/ThO2 < Pd/Ga2O3. The H-2 oxidation involved lattice oxygen from the oxidized catalysts. The catalyst activation results mostly from the oxidation of Pd metal from the catalyst producing bulk or sub-surface PdO. It also caused a drastic reduction in the H2O2 decomposition activity of the catalysts. There exists a close relationship between the H-2-to-H2O2 conversion activity and/or H2O2 selectivity in the oxidation process and the H2O2 decomposition activity of the catalysts; the higher the H2O2 decomposition activity, the lower the H-2-to-H2O2 conversion activity and/or H2O2 selectivity.
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| Publisher |
KLUWER ACADEMIC/PLENUM PUBLNEW YORK233 SPRING ST, NEW YORK, NY 10013 USA
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| Date |
2011-09-24T10:01:46Z
2011-09-24T10:01:46Z 2002 |
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| Type |
Article
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| Identifier |
CATALYSIS LETTERS
1011-372X http://hdl.handle.net/123456789/24227 |
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| Language |
English
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