Synthesis and Catalytic Performance of Mesoporous Material by Twostep Crystallization

A mesoporous material was synthesized by using the precursor of MCM22 zeolite through a twostep synthesis route, and characterized by XRD, N2 physical adsorptiondesorption, TEM, 27Al MAS NMR, IR spectra of pyridine adsorbed methods and so on. It was found that the synthesized sample was not a mixture of microporous zeolite and mesoporous material but a new mesoporous molecular sieve with strong acid sites and good thermal stability. The acid catalytic activity for macromolecules was evaluated and compared with conventional mesoporous material MCM-41 through the cracking reaction of cumene and alkylation reaction of benzene with 1dodecen. The results show that the conversions of cumene cracking at 350℃ over the new mesoporous material and MCM-41 are 68.98% and 48.80%, respectively. For the alkylation reaction of benzene with 1dodecen at 210℃, the conversions of 1dodecen over the new mesoporous materials and MCM-41 are around 95.20% and 86.89%, respectively. The selectivities of linear alkylbenzene over the new mesoporous materials and MCM-41 are around 88.11% and 90.06%, respectively. The results show that the catalytic property of the new mesoporous materials for macromolecules is superior to that of MCM-41.