View in EDS

Selective reduction of NO with CO in the presence of O2 with Ir/WO3 catalysts: Influence of preparation variables on the catalytic performance

Saved in:
Bibliographic Details
Title: Selective reduction of NO with CO in the presence of O2 with Ir/WO3 catalysts: Influence of preparation variables on the catalytic performance
Authors: Inomata, H.1, Shimokawabe, M.1, Kuwana, A.1, Arai, M. marai@eng.hokudai.ac.jp
Source: Applied Catalysis B: Environment & Energy. Dec2008, Vol. 84 Issue 3/4, p783-789. 7p.
Subjects: Nitrogen dioxide, Iridium, Catalysts, Chemical reduction
Abstract: Abstract: Several Ir/WO3 catalysts were prepared, which were different in the loading of Ir (up to 10wt.%) and in the pretreatment conditions, and used for the reduction of NO (500ppm) with CO (3000ppm) in the presence of excess O2 (5%), SO2 (2ppm), and H2O (1%). The rate of NO conversion per unit mole of Ir was found to be maximal at a small Ir loading of 0.5–1.0wt.%. The good catalytic performance was achieved when the Ir precursors (IrO x ) supported on WO3 were reduced under mild conditions by He at 400°C or H2/He at a lower temperature of 130°C. The catalysts were characterized by XRD, FTIR after CO adsorption, and H2-TPR. The characterization results show that the active sites are exposed zero-valent Ir species, in accordance with previous works using Ir on WO3 and other supports, and that the fraction of these active species is larger for a higher degree of Ir dispersion (smaller Ir particles). The preparation conditions for highly active Ir/WO3 catalysts were confirmed and possible reaction mechanisms were discussed. [Copyright &y& Elsevier]
Copyright of Applied Catalysis B: Environment & Energy is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Abstract: Several Ir/WO3 catalysts were prepared, which were different in the loading of Ir (up to 10wt.%) and in the pretreatment conditions, and used for the reduction of NO (500ppm) with CO (3000ppm) in the presence of excess O2 (5%), SO2 (2ppm), and H2O (1%). The rate of NO conversion per unit mole of Ir was found to be maximal at a small Ir loading of 0.5–1.0wt.%. The good catalytic performance was achieved when the Ir precursors (IrO x ) supported on WO3 were reduced under mild conditions by He at 400°C or H2/He at a lower temperature of 130°C. The catalysts were characterized by XRD, FTIR after CO adsorption, and H2-TPR. The characterization results show that the active sites are exposed zero-valent Ir species, in accordance with previous works using Ir on WO3 and other supports, and that the fraction of these active species is larger for a higher degree of Ir dispersion (smaller Ir particles). The preparation conditions for highly active Ir/WO3 catalysts were confirmed and possible reaction mechanisms were discussed. [Copyright &y& Elsevier]
ISSN:09263373
DOI:10.1016/j.apcatb.2008.06.011