Mechanism on Redistribution Synthesis of Dichlorodimethylsilane by
AlCl3/ZSM-5(3T)@γ-Al2O3 Core-shell Catalyst
Abstract
The redistribution method plays an important role in addressing the
issue of organosilicon by-product in the direct synthesis of
dichlorodimethylsilane, and the redistribution mechanism is still a
topic of debate. The redistribution by ZSM-5(3T)@γ-Al2O3 core-shell
catalyst and post-modified AlCl3/ZSM-5(3T)@γ-Al2O3 catalyst was
technically performed using the Density Functional Theory (DFT) at the
level of B3LYP/6-311++G(3df,2pd). The result shows that No.1 active site
of ZSM-5(3T)@γ-Al2O3 core-shell structure has a significant effect on
the activity of the catalyst. Indicating that the active center involved
in the reaction is H provided by Al-O-H bond, which is an obvious
catalytic active center of Bronsted acid. Furthermore, post-modified
AlCl3/ZSM-5(3T)@γ-Al2O3 catalyst is in more favor of redistribution
reaction comparing with ZSM-5(3T)@γ-Al2O3 core-shell catalyst. It
ascribes to the robust Lewis site of aluminum chloride favorable
modification.