Method and system for preparing tetramethyldihydrodisiloxane by hydrolyzing organic silicon low-boiling-point substance and comprehensive utilization method

Abstract

The invention discloses a method and a system for preparing tetramethyldihydrodisiloxane by hydrolyzing an organosilicon low-boiling-point substance and a comprehensive utilization method, and belongsto the field of organosilicon production. The method comprises the following steps: separating and purifying dimethyl monochlorosilane from a low-boiling-point substance, hydrolyzing the dimethyl monochlorosilane with higher content in a loop by using a hydrolysis process, and fully mixing reactants in the hydrolysis loop through a static mixer; wherein the temperature of process water is controlled to be about 10 DEG C through a cooler, and the hydrolysis temperature is controlled to be about 10 DEG C through a circulating cooler; then feeding the reaction mixture to a first layering devicethrough the top of a loop to achieve effective oil-water separation, and feeding hydrolysate (double seal heads) obtained through separation into a hydrolysate intermediate tank to be further settledand dewatered; and performing multi-stage washing and rectification on the crude hydrogen-containing double-end socket to obtain a qualified high-purity hydrogen-containing double-end socket product and 20% hydrochloric acid as a byproduct.

Description

Technical field: [0001] The invention relates to a method, a system and a comprehensive utilization method for preparing tetramethyldihydrodisiloxane by hydrolysis of organic silicon low-boiling substances, and belongs to the field of organic silicon production. [0002] technical background: [0003] At present, the direct synthesis method is mainly used to produce organosilicon monomers in China. The synthesized organosilicon monomers enter the distillation system to separate and extract dimethyldichlorosilane. Among them, a large number of mixed components with a boiling point below 40℃ are separated. The mixed components are defined as low boilers. The main component of low boilers is very useful Me 4 Si and Me 2 SiHCl, but it is difficult to separate due to the close boiling points of the components, and it is difficult to use. In addition, it can be directly hydrolyzed and alcoholyzed to prepare branched silicone oil. Foreign countries use low-boiling matter to produce gas p...

AI Technical Summary

Problems solved by technology

At present, many domestic manufacturers have built a disproportionation device, but the treatment of the disproportionated residue containing aluminum trichloride is cumbersome. Aluminum trichloride will react violently when it meets water, often accompanied by combustion. At the same time, the trichloride in the low boiling Hydrogen silicon does not react, so trichlorosilane will always circulate in the system, consumes a lot of energy, and accumulates in the device, eventually making it impossible to drive. At the same time, the silicon tetrachloride contained in the azeotrope does not react in the disproportionation device , so silicon tetrachloride will always circulate in the system and accumulate in the device

At present, low-boiling substances are mainly sold outside at a premium, and downstream manufacturers are unstable due to environmental protection control

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