A comparative investigation on the low-temperature catalytic oxidation of acetone over porous aluminosilicate-supported cerium oxides

Abstract

The performance of cerium oxide supported on mesoporous aluminosilicate particles (Al-MSPs) with a nominal Ce and Al loading of 2.8 and 1.2 wt.%, respectively, was evaluated for the low-temperature oxidation of acetone. The influence of the preparation methods, including one-step aerosol-assisted self-assembly (AASA) method and post-synthetic wet impregnation method, was examined. The results showed that the surface area and pore diameter of Ce/Al-MSPs(50/25) prepared by AASA method were similar to those of Ce-Al-MSPs made via traditional impregnation method, while a better metallic dispersion of Ce and Al oxide species on Ce/Al-MSP5(50/25) was observed as compared to that of Ce-Al-MSPs. The catalytic performances of Ce/Al-MSPs(50/25) and Ce-Al-MSPs were compared with that of cerium-impregnated H-ZSM-5 (Ce-ZSM-5) zeolite catalyst. The activity of freshly made catalysts followed the order: Ce/Al-MSPs(50/25) > Ce-ZSM-5 > Ce-Al-MSPs. The superior catalytic behavior of the Ce/Al-MSPs(50/25) could be due to the combined effect of strong surface reducibility and high acid property. Although Ce-ZSM-5 and Ce-Al-MSPs presented high activity for acetone removal in the beginning, their activities quickly decreased due to the coking effect. In contrast, Ce/Al-MSP5(50/25) showed a good stability during a 24 h test at the reaction temperature of 150 degrees C. Both surface reducibility and acidity played crucial roles for their high catalytic performance and high stability at low temperatures. (C) 2014 Elsevier B.V. All rights reserved.