氯甲烷在镁修饰的ZSM-5分子筛催化剂上催化转化研究

Chloromethane Conversion over Mg Modified ZSM-5 Zeolite Catalysts

在镁修饰的ZSM-5分子筛催化剂上,氯甲烷可以被催化转化为烃类产品。分别采用了离子交换和浸渍的方法来修饰ZSM-5分子筛。离子交换的Mg-ZSM-5催化剂和浸渍的Mg/ZSM-5催化剂都可以提高反应产物中的低碳烯烃的选择性,降低烷烃的选择性,并且保持较高的反应活性,但高的浸渍量对反应活性有一定的影响。NH3-TPD的结果表明,浸渍镁的ZSM-5催化剂的强酸中心数目明显减少。镁的修饰对催化剂酸性的影响导致了产物中低碳烯烃的增加。浸渍Mg的ZSM-5催化剂是潜在氯甲烷转化生成低碳烯烃的催化剂。

Chloromethane was catalytically converted to higher hydrocarbons over Mg modified ZSM-5 catalyst. Two methods, ion-exchanging and impregnation, were utilized to prepare the catalysts. It was demonstrated that Mg modification could increase the olefins selectivity, decrease the paraffins selectivity, and yield high activity in the chloromethane transformation reaction, while excessive modification caused activity loss. The acid property of impregnated Mg/ZSM-5 catalysts was observed in NH3-TPD. The improvement of light olefins selectivity resulted from the effect of Mg impregnation on the acid property. The Mg modified ZSM- 5 are potential catalysts for chloromethane transformation to light olefins.