The Ba-hemaluminate doped with CeO2 nanoparticles for catalytic combustion of methane

The Ba-hexaaluminate doped with CeO2 nanoparticles with high surface area for catalytic combustion have been prepared by using the alumina sol as the (NH4)2CO3 coprecipitation precursor and supercritical drying method. The catalysts are composed of the rod-like particles and granular ones. The CeO2/BaAl12O19-alpha catalyst possesses the highest surface area (83.5 m(2)/g) and the smallest CeO2 mean crystallite size (24.3 nm). Introduction of transition metal ion into the Al2O3 spinel leads to the increase of the catalytic activity. Nevertheless the hexaaluminate cannot be obtained when further increasing the introduction, the components of the main crystalline phases are Al2.267O4 and CeO2. The CeO2/BaFeMnAl10O19-alpha catalyst possesses the lowest complete conversion of methane temperature, probably due to the high surface area and the excellent performance of activating oxygen. (c) 2006 Elsevier B.V. All rights reserved.