Title of Paper:Highly catalytic activity of Mn/SBA-15 catalysts for toluene combustion improved by adjusting the morphology of supports

Hits:

Date of Publication:2019-02-01

Journal:JOURNAL OF ENVIRONMENTAL SCIENCES-CHINA

Included Journals:PubMed、EI、SCIE

Volume:76

Page Number:208-216

ISSN No.:1001-0742

Key Words:Mn/SBA-15; Morphology; Lattice oxygen; Oxygen mobility

Abstract:Rod-like, hexagonal and fiber-like SBA-15 mesoporous silicas were synthesized to support MnOx for toluene oxidation. This study showed that the morphology of the supports greatly influenced the catalytic activity in toluene oxidation. MnOx. supported on rod-like SBA-15 (R-SBA-15) displayed the best catalytic activity and the conversion at 230 degrees C reached more than 90%, which was higher than the other two catalysts. MnOx species consisted of coexisting MnO2 and Mn2O3 on the three kinds of SBA-15 samples. Large amounts of Mn2O3 species were formed on the surface and high oxygen mobility was obtained on MnOx supported on R-SBA-15, according to the H-2 temperature programmed reduction (H-2-TPR) and X-ray photoelectron spectroscopy (XPS) results. The Mn/R-SBA-15 catalyst with greater amounts of Mn2O3 species possessed a large amount of surface lattice oxygen, which accelerated the catalytic reaction rate. Therefore, the surface lattice oxygen and high oxygen mobility were critical factors on the catalytic activity of the Mn/R-SBA-15 catalyst. (C) 2018 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.