Device and method for producing silane by disproportionated reaction distillation of trichlorosilane

Abstract

The invention relates to a device and method for producing silane by disproportionated reaction distillation of trichlorosilane. The device is a distillation tower; the distillation tower is provided with a distillation section, a reaction section and a stripping section; a tower-top deep freezer is arranged on the distillation section; a tower kettle is provided with a reboiler; the distillation section and the stripping section are internally provided with structured packing; the reaction section is internally provided with a structure catalyst; a tower-top condenser and the distillation section are respectively provided with a vacuum jacket and an insulating layer; the vacuum jackets of the tower-top condenser and the distillation section are respectively provided with a vacuum extraction opening; the reaction section and the stripping section are provided with insulating layers; a silane outlet is arranged at the tower top; the tower-top deep freezer is provided with a tower-top condensate inlet and a tower-top condensate outlet; and a trichlorosilane inlet is arranged under the reaction section. Compared with a multi-step disproportionation process, the process has the advantages that the equipment is simple, the multi-step disproportionation reaction can be realized only by one reaction distillation tower, silicon tetrachloride as a product of the tower kettle returns into a cold hydrogenation system and is converted into the trichlorosilane, so that the closed-loop circulation is realized and simultaneously the purity of the obtained silane is high.

Description

technical field [0001] The present invention relates to a device and method for generating silane through disproportionation reaction rectification of trichlorosilane, in particular to a device and method for producing silane through disproportionation reaction rectification by using trichlorosilane as raw material, adding condensation in the middle section, and utilizing reactive rectification technology. Silane apparatus and methods. Background technique [0002] Silane, English name: silane, molecular formula is SiH 4 . As an important silicon source material, silane is widely used in semiconductor microelectronic IC, photovoltaic solar cell PV, liquid crystal display LCD and other industries. [0003] At present, there are three main production methods of silane: sodium aluminum fluoride method, silicon-magnesium alloy method and chlorosilane disproportionation method. Among them, the sodium aluminum fluoride method uses sodium aluminum hydride and silicon tetrafluori...

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Problems solved by technology

[0005] There are certain defects in the existing foreign chlorosilane disproportionation technology to prepare silane: firstly, the multi-step disproportionation process equipment using fixed bed matching rectification sequence is complex, and because the boiling point of silane at normal pressure is extremely low, about -112°C, silane The operating pressure of the purification tower is high, generally higher than 5Mpa, the temperature at the top of the tower is low, generally lower than -110°C, and the cost of condensing refrigerant at the top of the tower is relatively high; secondly, the simplified disproportionation reaction distillation process, although the process equipment is simplified, However, it also faces the problem of low-temperature condensation, and the process is more difficult to realize

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