Catalytic disproportionation of trimethoxysilane to monosilane: Studies on catalyst, kinetics and reactor modeling

• A K 2 CO 3 /γ-Al 2 O 3 catalyst for disproportionation of trimethoxysilane was designed. • The constant 97.6 % selectivity and 71.6 % conversion within 300 h were obtained. • Kinetics modeling, reaction mechanism, and reactor simulation were investigated. Monosilane is an indispensable special gas used in semiconductor, photovoltaic, LED, TFT, and lithium-ion battery industries. In this work, a chlorine-free route for monosilane by the disproportionation of trimethoxysilane (TMS) was investigated with a novel efficient and stable solid alkaline catalytic system composed of γ-Al 2 O 3 supported K 2 CO 3 . TMS conversion of 71.6 % and silane selectivity of 97.6 % were obtained on the 15K 2 CO 3 /γ-Al 2 O 3 catalyst with a high WHSV of 8 h −1 , which could be operated stably over 300 h. Furthermore, the reaction kinetic model was established based on the E-R mechanism and a catalytic pathway was proposed according to kinetic results and DFT calculation. A novel reactive distillation reactor with cascaded condensers for silane production was simulated by using Aspen Plus. The results showed that the energy consumption of TMS disproportionation is much lower than that in TCS disproportionation.