CO偶联反应Pd/α-Al_2O_3催化剂失活的XPS研究

XPS study on the deactivated Pd/α-Al_2O_3 catalyst for CO coupling reaction with ammonia

利用失活Pd/α Al2O3催化剂的X 光电子能谱(XPS)探讨了氨气引起Pd/α Al2O3催化剂失活的原因.分析认为氨分子在活性组分Pd2+上的竞争吸附阻碍了催化剂表面上CO偶联反应及活性组分Pd的氧化还原循环,导致催化剂活性下降.

The mechanism of ammonia poisoning for Pd/α-Al_2O_3 catalyst was discussed on the basis of XPS measurement results of the catalyst. It was found to be the competitive adsorption of ammonia on Pd^(2+) of catalytic surface inhibiting CO coupling reaction and the cycle of oxidation and reduction of active component —Pd on the catalyst surface. Therefore, the feed gas with ammonia causes the catalyst activity to decrease.