季铵盐功能化的钛硅分子筛催化丙烯氧化酯化合成碳酸丙烯酯

Synthesis of Propylene Carbonate on a Bifunctional Titanosilicate Modified with Quaternary Ammonium Halides

将有机卤素季铵盐以硅烷化键合方式嫁接到钛硅分子筛上,制备了兼备催化氧化烯烃合成环氧化物和环氧化物碳酸酯化反应的新型双功能催化剂,考察了其在丙烯、过氧化氢和二氧化碳一步合成碳酸丙烯酯的催化性能.研究表明,具有大外表面积的层剥离的钛硅分子筛是一种嫁接季铵盐合适的载体,丙基三丁基卤化铵是酯化催化性能优良的功能化基团,两者的偶合使一步法催化丙烯环氧化酯化合成碳酸丙烯酯的收率达48%.该催化剂具有较好的稳定性和重复使用性能.

A novel bifunctional catalyst that exhibits catalytic activity for both the epoxidation of olefins and the carbonation of organic epoxides has been prepared through grafting quaternary ammonium halide on a titanosilicare. The one-pot synthesis of propylene carbonate from propylene, hydrogen peroxide, and carbon dioxide has been investigated. Delaminated titanosilicate with an open external surface is an excellent support for the immobilization of quaternary ammonium salts, and propyl tributyl ammonium halides are active functional species for the cycloaddition. The combination of delamination and functionalization leads to an active catalyst giving a yield of propylene carbonate as high as 48 % and good stability and reusability.