1,2 -二氯乙烷在担载铈钛复合氧化物的蜂窝陶瓷催化净化——催化组分颗粒大小的影响

采用溶胶-凝胶法制备担载 TiO2 和 CeTiOx 复合氧化物涂层的堇青石蜂窝陶瓷整体式催化剂,并考察 1,2-二氯乙烷(DCE)在上述催化剂上的催化效果。结果表明:TiO2 和 CeTiOx 复合氧化物涂层材料对DCE 的催化燃烧均具有很好的催化活性, 前者在 400 ℃时,DCE 的转化率为 93.1%,后者已达 98.5%,可见,CeTiOx 可以更有效地催化燃烧处理 DCE。譬如,在 300 ℃时,在 CeTiOx 涂覆的催化剂上 DCE 的转化率为 85.6%。但随着催化剂处理温度的升高,CeTiOx 催化活性组分的颗粒变大,导致 CeTiOx 蜂窝陶瓷催化剂对于 DCE 的催化活性降低。

Catalytic Purification of 1,2-Dichloroethane on CeTiOx-Cordierite Honeycomb Catalysts——Influence of Particle Sizes of Catalytic Components

The cordierite honeycomb ceramics were coated with TiO2 and CeTiOx oxides prepared by sol-gel method, and their catalytic activities on catalytic combustion of 1, 2-dichloroethane(DCE) were investigated. The results showed that the catalysts exhibit high catalytic activity, e. g., the combustion conversion of 1, 2-DCE was 93.1% and 98% at the reaction temperature of 400 ℃ on the TiO2 coated catalyst and the CeTiOx coated catalyst, respectively. It was observed that at even lower temperature such as 300 ℃ ,the combustion conversion of 1, 2-DCE was 85.6% on the CeTiOx coated catalyst, which was very close to the best performance on non-noble metal catalysts for the reaction. The catalysts were characterized by XRD, SEM and BET, and it was observed that the activity of the catalysts was markedly related to particle size of active species on the catalysts. The particles of CeTiOx active species grew larger with increasing the calcination temperature, which led to a decrease in the activity of 1, 2-DCE combustion.