A STUDY ON AERGOEL CATALYST MIXED BY CERIA AND MANGANESE OXIDES
锰铈混和氧化物气凝胶催化剂的研究

In this paper, CeO_2 aerogel and Ce_(1-x)Mn_xO_2 aerogel (x=0.05, 0.10, 0.15,0.20) were prepared by sol-gel method and super critical fluid drying technology. Mn/CeO_2 was prepared by impregnating CeO_2 aerogel with the solution of manganese nitrate. The prepared aerogels were characterized by TEM, BET, CO oxidation reaction and H_2-TPR. The experimental results of TEM and BET showed that with the increase of manganese content, the particle size of ceria aerogel decreased and the surface area increased. Reaction of CO oxidation showed that the oxidation activity was improved by adding Mn to the ceria aerogel. The best result was gained when the Mn content is 15mol%. Ce_(1-x)Mn_xO_2 aerogel (x=0.05, 0.10, 0.15,0.20) and Mn/CeO_2 show different carbon monoxide oxidation activities. Catalyst prepared by impregnation method (Mn/CeO_2) shows lower catalyst activity than CeO_2 and Ce_(1-x)Mn_xO_2(x=0.05, 0.10, 0.15,0.20) areogel. TPR experiment shows Mn species on ceria are also reduced through three steps as MnO_2.