Ti-MCM-41 synthesized from colloidal silica and titanium trichloride: Synthesis, characterization, and catalysis

Titanium-containing mesoporous molecular sieve Ti-MCM-41 has been synthesiz ed using colloidal silica as the silicon source and TiCl3 solution as the t itanium source and was characterized by X-ray diffraction, N-2 adsorption, UV-vis, and UV-Raman spectroscopies. The formation of anatase TiO2 can be a voided during the synthesis and the crystallization of the molecular sieve because of the relatively low hydrolysis rate of an inorganic TiCl3 solutio n. The characterization results confirm that most Ti4+ ions are isolated an d tetrahedrally coordinated in the framework of MCM-41. Different auxiliary templates, tetramethylammonium hydroxide (TMAOH), tetraethylammonium hydro xide (TEAOH), tetrabutylammonium hydroxide, and NH3. H20 were used to synth esize the Ti-MCM-41 molecular sieve. Among them, TMAOH and TEAOH were found to be the most effective auxiliary templates to improve the long-ranged or der of the molecular sieves.