Reactive Distillation Column for Disproportionation of Trichlorosilane to Silane: Reducing Refrigeration Load with Intermediate Condensers

Abstract

This paper presents a reactive distillation column for the catalytic disproportionation of trichlorosilane to silane which includes three consecutive reversible reactions with a thermodynamic conversion to silane as low as 0.2% and is of no practical significance using the conventional reactors. This reaction system is however characterized by a large distinction in the boiling points of the components, which makes the reactive distillation extremely favored. Nevertheless, the normal reactive distillation column possesses the shortage of high refrigeration requirement as the standard boiling point of the overhead product silane is −112 °C. A novel reactive distillation column with intercondensers placed within has been simulated using Aspen Plus package for a feasible alternative to alleviate this drawback. The calculated results show that a reduction in the refrigeration load of more than 97% can be obtained when one intermediate condenser is inserted between the rectifying and reaction zones, and that another normal intermediate condenser equipped within the reaction section can further decrease the condensation requirement of the first intermediate condenser by 50%. Effects of the configuration parameters and operational conditions have also been investigated for optimal design and operation of the proposed reactor.