Post-synthetic preparations of titanium-containing mesopore molecular sieves

摘要

Titanium-substituted mesoporous molecular sieves were prepared post-synthetically by applying Ti-butoxide in ethanol solutions of different concentrations to MCM-41, MCM-48, and KIT-1. The catalysts obtained were characterized by XRD, FT-IR, UV-Vis spectroscopies, XAS, and N_2 physisorption. Incorporation of Ti seems to promote further crosslinking of the mesoporous walls of the samples, and resulted in wall thickness increases. The post-synthetically prepared Ti-mesoporous derivatives using titanium butoxide grafting were catalytically active for the selective oxidation of 2,6-di-tert-butylphenol with H_2O_2. Their activities depended on the Ti concentration of the catalysts. Comparison works with hydrothermally prepared Ti-MCM-41, Ti-HMS or post-synthetically prepared Ti-mesopore catalysts, either using titanocene grafting or by TiCl_4 atom planting method, are also reported.