Method and system for removing ethyl hydride in dimethyl dichlorosilane crude product

Abstract

The invention provides a method and system for removing ethyl hydride in a dimethyl dichlorosilane crude product. The method comprises the following steps of: adding the dimethyl dichlorosilane crude product and hydrogen chloride into an ethyl hydride conversion reactor in a gaseous form; and carrying out catalytic conversion reaction in the reactor, so as to chloridize the ethyl hydride in the dimethyl dichlorosilane crude product, and removing the chloridized ethyl hydride through rectification. The catalyst used in the method and system of the invention has excellent selectivity, thermal stability and no corrosion to carbon steel, and can effectively chloridize the ethyl hydride in the dimethyldichlorosilane, and the boiling point of the chloridized ethyl hydride is increased, so that the ethyl hydride in the dimethyldichlorosilane can be removed through a conventional rectification mode, the stability of a downstream product and the feasibility of a downstream production process are ensured. Meanwhile, the ethyl hydride conversion reactor used in the method and system of the invention has the advantages of long device operation cycle and short starting time.

Description

technical field [0001] The invention relates to the technical field of organosilicon synthesis, in particular to a method and system for removing ethyl hydride in crude dimethyldichlorosilane. Background technique [0002] The organosilicon industry is developing rapidly, and the market demand is increasing every year. At present, the total output of organosilicon monomers in my country has leapt to the first in the world. At the same time, my country also imports a large amount of high-quality organosilicon monomers every year. [0003] At the end of monomer synthesis fluidized bed operation, as the yield of dimethyldichlorosilane (dimethyl) decreases, some impurities will also be produced, including ethyl hydride (Ethylhydrodichlorosilane), which has a small content and belongs to "ppm" level, but when the ethyl hydride content in pure dimethylformamide exceeds 4ppm, it will affect the after-system, and it is easy to cause structure in the hydrolysis process, and it is dif...

AI Technical Summary

Problems solved by technology

[0003] At the end of monomer synthesis fluidized bed operation, as the yield of dimethyldichlorosilane (dimethyl) decreases, some impurities will also be produced, including ethyl hydride (Ethylhydrodichlorosilane), which has a small content and belongs to "ppm" level, but when the ethyl hydride content in pure dimethylformamide exceeds 4ppm, it will affect the after-system, and it is easy to cause structure in the hydrolysis process, and it is difficult to eat powder in the mixed gel processing process

At the same time, the ethyl hydrochlorosilane in dimethyldichlorosilane will also cause instability of downstream products, and color difference, such as yellowing, etc., so the ethyl hydride must be removed

However, since the boiling point of ethyl hydride (EtH) is very close to that of dimethyldichlorosilane (90°C), it is difficult to remove it from dimethyl by conventional distillation methods.

Images