DFT study on the disproportionation of methylchlorosilane catalyzed by AlCl3/ZSM-5(4T)@MIL-53(Al) core-shell catalyst

Abstract

Dimethyldichlorosilane is one of the most widely used monomers in the organic silicon industry chain. In the preparation process, it can be obtained by exchanging functional groups through disproportionation reaction. In this research, the disproportionation mechanism catalyzed by ZSM-5(4T)@MIL-53(Al) and AlCl3/ZSM-5(4T)@MIL-53(Al) core-shell catalysts was studied by using the density functional theory on the level of M06-2X/Def2-TZVP. The results showed that the two catalysts possessed different catalytic effect assigning to different acidic actives. The surface activity of ZSM-5(4T)@MIL-53(Al) core-shell catalyst modified by AlCl3 became the Lewis acid center of Al-Cl bond, which had better disproportionation activity than that before modification. Energies, frequency vibrations and IRC calculations, bond orders, ELF and LOL analyses can verify the reaction mechanism proposed in this research.