A Novel Method for Incorporation of Heteroatoms into the Framework of Ordered Mesoporous Silica Materials Synthesized in Strong Acidic Media

Abstract

Heteroatoms of Al and Ti are effectively introduced into the framework of ordered mesoporous silica materials (designated as MAS-7 and MTS-9, respectively) in strong acidic media (pH < 0) by a two-step procedure. MAS-7 shows high catalytic activities for the cracking of both small (cumene) and bulky (1,3,5-tri-isopropylbenzene) molecules because it combines the advantages of both zeolites (strong acidity) and mesoporous materials (large pores). In contrast, Al-SBA-15 samples prepared from both "post-synthesis" and "direct synthesis" present much lower catalytic activities than MAS-7. Furthermore, MTS-9 exhibits very high catalytic activity in phenol hydroxylation by H2O2, giving the phenol conversion of 26%, comparable to TS-1.