Saturated acid hydrolysis technology of alkylchlorosilane

Abstract

The invention provides saturated acid hydrolysis technology of alkylchlorosilane. The first step is a saturated acid hydrolysis reaction, hydrogen chloride gas obtained through saturated acid hydrolysis can return to a chlorosilane synthesis working section through a demister, saturated acid after separation through a phase separator of the saturated acid hydrolysis returns to a saturated acid water hydrolysis device, and hydrolysate is performed according to the second step. The second step is a diluted acid hydrolysis reaction, the alkylchlorosilane without complete hydrolysis further reacts with diluted acid, and a diluted acid hydrolysis reaction comprises a diluted acid hydrolysis strengthening reactor and a diluted acid hydrolysate phase separator. Circulating diluted hydrochloric acid after being separated through the diluted acid hydrolysis phase separator is supplemented in the saturated acid hydrolysis device, and hydrolysate is performed according to the third step. The third step is steam dechlorination, chlorine concentration in coarse hydrolysate is reduced, the steam dechlorination comprises a steam dechlorination tower, a material phase separator is arranged on a tower top of the steam dechlorination tower, and a discharging material phase separator is arranged at a tower bottom of the steam dechlorination tower. Qualified polyalkysiloxane can be obtained through the three-step technology.

Description

technical field [0001] The invention relates to a device and a hydrolysis process for generating hydrogen chloride gas and polyalkylsiloxane through a three-step hydrolysis process of alkyl chlorosilane under saturated acid conditions. Background technique [0002] The hydrolysis of alkyl chlorosilanes produces alkyl silanols and hydrogen chloride. The reaction itself is an endothermic reaction, but because HX is dissolved in water to generate a lot of heat, the hydrolysis of alkyl chlorosilanes is an exothermic process. The rate of the hydrolysis reaction of organosilanes increases with the increase in the polarity and number of Si-X bonds, but slows down with the increase in the steric hindrance and the increase in the number of organic groups. Chlorine-terminated polysiloxanes can be obtained when alkylchlorosilanes are hydrolyzed in insufficient water. [0003] Dimethyldichlorosilane, Me 2 SiCl 2 For example, Me 2 Si(OH) 2 , Advanced intermolecular condensation to g...

AI Technical Summary

Problems solved by technology

[0011] 1. At a high concentration of hydrogen chloride, a layer of hydrogen chloride gas film will be formed on the surface of organochlorosilane particles, making it difficult for water molecules to fully contact with organochlorosilane molecules, thus reducing the rate of hydrolysis reaction

[0012] 2. Before the hydrolysis reaction is complete, the molecules of organochlorosilane will diffuse into hydrogen chloride gas and be taken out

Therefore, while reducing the yield, it also affects the purity of hydrogen chloride gas, which has a certain impact on the synthesis of methyl chloride

[0013] 3. Saturated acid hydrolysis may also produce chlorine-containing linear siloxane at the end, which will affect the quality of the hydrolyzate and further affect the quality of subsequent downstream products

The mixing efficiency of this static mixing reaction material is low, and the hydrogen chloride gas is difficult to volatilize, which easily makes the concentrated acid appear in a supersaturated state after the reaction.

[0015] Aiming at the shortcomings of low stirring efficiency, uneven mixing, long reaction time, low product purity and high material consumption and energy consumption in the above process, a saturated acid hydrolysis process of alkyl chlorosilane is provided

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