Characterization of AlSBA-15 prepared by post-synthesis alumination with trimethylaluminium

The mesoporous siliceous SBA-15 molecular sieve was synthesized and post-synthesis alumination was carried out using trimethylaluminium (TMA). It was found that the aluminium could be easily incorporated into the siliceous framework of SBA-15 without serious structure deformation. From detailed characterization of the prepared aluminium-containing SBA-15 (AlSBA-15) it was also found that it is difficult to keep the aluminium in the framework position after calcination. The hydrothermal stability of SBA-15 was considerably improved by the TMA processing. The results of the cumene cracking reactions and the pyridine adsorption experiments indicated that the Bronsted acid sites of AlSBA-15 are stronger than those of AlMCM-41 prepared by the same method.