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Indexed by:期刊论文

Date of Publication:2011-11-01

Journal:CHEMICAL ENGINEERING & TECHNOLOGY

Included Journals:Scopus、SCIE、EI

Volume:34

Issue:11

Page Number:1864-1868

ISSN No.:0930-7516

Key Words:Soot oxidation; Nitric oxide; Potassium; Hydrotalcite; Ketene group; Nitrite

Abstract:Soot oxidation with NO (in the absence of gas phase O-2) on potassium-supported Mg-Al hydrotalcite mixed oxides (K/MgAlO) was studied using a temperature-programmed reaction and in situ FTIR techniques. Nitrite and the ketene group were identified as the reaction intermediates and thus a nitrite-ketene mechanism was proposed in which surface active oxygen on K sites of K/MgAlO is transferred to soot by NO through nitrites. In the absence of gas phase O-2, soot oxidation with NO at lower temperatures (below 450 degrees C) is limited by the amount of active oxygen on the K sites. This kind of active oxygen is not reusable but can be replenished in the presence of gas phase O-2.