ISSN:
0009-286X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Kinetic aspects of the catalytic detoxification of automobile exhaust. The technology of catalytic converters designed to reduce automobile exhaust emissions has developed considerably in recent years, as is well documented in the available literature. This review is intended to show how the methodology and philosophy of chemical reaction engineering have contributed to this development. A brief survey of possible reactions and actual catalysts is followed by a detailed account of the relevant basic principles of micro- and macrokinetics. Preliminary calculations of conversion of noxious substances in monolithic converters may be based upon the assumption that diffusion from the laminarly flowing gas phase to the catalytically active wall coating is the rate-determining step in a warmed-up converter. During the critical warm-up period, after a cold start, the chemical reaction steps offer the main resistance. The points discussed are the extent to which rate equations and kinetic parameters will be influenced by high degrees of dispersion of the noble metals, by catalyst deactivation, or by transient operation conditions. The structure of the highly porous catalyst support as well as metal impregnation profiles can be optimized so that poisoning is strongly retarded by in-pore diffusion, while the main reactions are affected as little as possible.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cite.330571004
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