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Indexed by:期刊论文

Date of Publication:2014-01-01

Journal:JOURNAL OF CATALYSIS

Included Journals:SCIE、EI

Volume:309

Page Number:268-279

ISSN No.:0021-9517

Key Words:Hydrotalcite-like compounds; CuTi-mixed oxide; Selective catalytic reduction; In situ Fourier transform infrared

Abstract:A series of hydrotalcite-based CuxTi1 (x = 2, 3, 4, 5)-mixed oxide catalysts have been synthesized by homogeneous precipitation and tested in the selective catalytic reduction (SCR) of NO by C3H6 in the presence of excess oxygen. Cu atoms can be categorized into surface and bulk species. The surface Cu species are the active sites while the bulk Cu species possess adsorption property for nitrogen species, and such bulk Cu species varies from CuxTiyOz to CuO with increasing Cu content. The Cu3Ti1 catalyst with the highest amount of surface copper and Lewis acid sites exhibits the best catalytic performance due to its improved electrophilicity of CuxTiyOz, which enhance the adsorption capability of nitrogen species. In situ infrared characterization revealed that nitrates in terms of bridging, bidentate and chelating species are reactive toward acetate and formate, and they are the key intermediates produced during the SCR of NO. (C) 2013 Elsevier Inc. All rights reserved.