CuO(-CeO_2)/SBA-15对萘氧化的催化活性及CO_2选择性研究

通过浸渍法制备CuO/SBA-15和CuO-CeO2/SBA-15两种介孔材料催化剂,采用BET、XRD、TPR和XPS等对催化剂进行表征,重点考察催化剂对萘氧化反应的催化活性及对产物CO2的选择性。BET、XRD和XPS等实验结果表明CuO高度分散于介孔分子筛SBA-15中,CeO2可促进CuO在载体上的分散,同时能降低催化剂的TPR还原温度。活性测试结果表明CuO/SBA-15对萘氧化反应的催化活性较高,但是催化氧化的CO2选择性较低,温度在380℃时CO2的生成率仅为60%左右;CeO2的添加不仅提高了CO2的生成率,15%CuO-15%CeO2/SBA-15在325℃使CO2生成率达到99%,而且CeO2增强了催化剂的稳定性。

Study on catalytic activity and CO2 selectivity for naphthalene oxidation over CuO(-CeO2)/SBA-15

CuO and CuO-CeO_2supported mesoporous molecular sieves SBA-15 were prepared using an im-pregnation method, and the catalysts were characterized by BFT,XRD,TPR and XPS techniques. The catalytic activity and CO_2 selectivity for the complete oxidation of naphthalene were investigated. The results show that CuO is dispersed highly on the mesoporous molecular sieves, CeO_2improves CuO dispersion and lower TPR re-duction temperature. Besides, the total conversion of naphthalene to CO_2 is not achieved over the CuO/SBA-15catalyst and CO_2 yield is 60% at 380 ℃ . It is concluded that CeO_2 plays an important role in promoting carbon balance and catalyst stability. Naphthalene conversion to CO_2 of 99% is obtained over the 15% CuO-15% CeO_2/ SBA-15 catalyst at 325 ℃ .