论文部分内容阅读
本文介绍了一种新颖的沸石分子筛合成方法——气相法合成ZSM-5(G-ZSM-5),该方法能直接合成出反应所需的SiO_2/Al_2O_3沸石,而无硅铝损失,有机胺可循环使用,从而消除了废水的污染。本文考察了Na_2O/Al_2O_3比对G-ZSM-5的酸性和活性的影响;研究了焙烧顺序,温度及交换溶液对G-ZSM-5酸性和活性的影响。随焙烧温度增加,邻二甲苯异构化活性及G-ZSM-5酸性下降。随酸中心数增加,邻二甲苯异构化活性增加,弱酸中心数的增加有利于对二甲苯的生成。
In this paper, a new synthesis method of zeolite molecular sieve-gas phase synthesis of ZSM-5 (G-ZSM-5) is introduced. This method can directly synthesize the desired SiO 2 / Al 2 O 3 zeolite without loss of silica- Recyclable, eliminating waste water pollution. The effect of Na 2 O / Al 2 O 3 ratio on the acidity and activity of G-ZSM-5 was investigated. The effects of roasting sequence, temperature and exchange solution on the acidity and activity of G-ZSM-5 were investigated. With the increase of calcination temperature, the o-xylene isomerization activity and the acidity of G-ZSM-5 decreased. As the number of acid sites increases, the o-xylene isomerization activity increases and the increase of the number of weak acid sites is favorable for the formation of p-xylene.