钛硅沸石的制备及其选择氧化性能

采用水热晶化法和气固相同晶取代法成功地合成了Ｔｉ－ＺＳＭ－５和Ｔｉ－ＺＳＭ－１１型分子筛；应用苯酚羟基化，苯乙烯氧化和丙烯环氧化反应为探针，详细考察了不同方法合成的钛硅沸石的催化性能。

Preparation and selective oxidation properties of titanium silicalite

Ti ZSM 5 and Ti ZSM 11 type molecular sieves have been successfully synthesized with hydrothermal synthesis and gas solid isomorphous replacement. The catalytic properties of titanium silicalite synthesized with different methods were studied in detail using phenol hydroxylation, styrene oxidation and propylene epoxidation as test reaction. The results show that, using the titanium silicalite synthesized with cheap templating agent to catalyze the hydroxylation of phenol, the conversion of phenol is 20% 30% (the molar ratio of phenol to H 2O 2 is 1). Moreover, the conversion of phenol decreases drastically with the increase in the molar ratio of phenol to H 2O 2. In the titanium silicalite synthesized with TiCl 4 substitution method, the environment of titanium atom incorporating into the framework is different from that synthesized with hydrothermal method. Using this catalyst in the oxidation of styrene, the conversion of styrene is up to 40%, and the selectivity of aromatic aldehyde is up to 90% (the molar ratio of styrene to H 2O 2 is 2.2). Using this catalyst in the epoxidation of propylene, it can high selectively produce propylene oxide. The physical chemical properties of titanium silicalite synthesized with cheap templating agent are similar to that of TS 1. However, the physical chemical properties are not proportional to the catalytic properties.