Preparation technology of methyl triethoxysilane

Abstract

The invention discloses a preparation technology of methyl triethoxysilane. Methyldichlorosilane and absolute ethyl alcohol are adopted as the raw materials, and the technology comprises the four steps of alcoholysis, deacidification, separation of crude products and refinement, and comprises the following specific steps: carrying out alcoholysis reaction on methyldichlorosilane and absolute ethyl alcohol subjected to vaporization and steam stripping in an alcoholysis reaction tower; introducing the product mixture into a stripping tower for steam stripping of unreacted methyldichlorosilane and HCl, conveying the product mixture subjected to steam stripping into a neutralization kettle, and further removing HCl through the action of a neutralizer; after neutralization, filtering for salt removal to obtain a crude product of methyl triethoxysilane; carrying out rectification on the crude product for purification to obtain a colorless and transparent methyl triethoxysilane product. According to the preparation technology, the use of an organic solvent is avoided, the reaction is mild, the side reaction is less, and the product content is high; the recycling of the monomer by-product, namely, methyldichlorosilane, is effectively realized, and the additional value is increased; the devices used in the technology are conventional devices, the operation is easy to control, the pollutant emission during the whole reaction process is less, and the preparation technology is quite suitable for industrialized and enlarged production.

Description

technical field

[0001] The invention relates to a preparation process of organosilane, in particular to a preparation process of methyltriethoxysilane. Background technique

[0002] Methyltriethoxysilane is a common organosilicon material widely used in the rubber and pharmaceutical industries, mainly as a crosslinking agent for room temperature vulcanized silicone rubber, a glass fiber coupling It is used as an end-capping agent for siloxane polymers, and is also one of the important raw materials for the production of silicone resin, benzyl silicone oil, and waterproofing agent.

[0003] At present, the conventional preparation process of methyltrialkoxysilane is to prepare methyltrichlorosilane and ethanol through esterification reaction, and generate hydrogen chloride gas at the same time. However, during the alcoholysis reaction between methyltrichlorosilane and alcohol, the substitution reaction of the third chloro group in methyltrichlorosilane is very difficult, and...

Examples

Embodiment 1

[0032] A. alcoholysis

[0033] 150 parts by weight of methylhydrogendichlorosilane is first vaporized through a vaporizer, and then enters the bottom of the alcoholysis reaction tower through a stripper, and 190 parts by weight of absolute ethanol is added into the alcoholysis reaction tower in liquid form from the top inlet of the alcoholysis reaction tower , the upward gaseous methylhydrogendichlorosilane and the downward liquid anhydrous ethanol are fully contacted, alcoholysis reaction and hydrogen substitution occur, and methyl triethoxysilane and by-product hydrogen chloride are generated; the temperature control of the vaporizer and the stripper All at 55°C; alcoholysis reaction temperature is 45°C;

[0034] Most of the hydrogen chloride escapes through the outlet at the top of the alcoholysis reaction tower, and the remaining hydrogen chloride forms a product mixture with the reaction product;

[0035] B. Neutralization

[0036] Keep the temperature in the stripping ...

Embodiment 2

[0042] Change alcoholysis reaction temperature to be 60 ℃, all the other are the same as embodiment 1.

Embodiment 3

[0044] Change alcoholysis reaction temperature to be 70 ℃, all the other are the same as embodiment 1.

technical field

[0001] The invention relates to a preparation process of organosilane, in particular to a preparation process of methyltriethoxysilane. Background technique

[0002] Methyltriethoxysilane is a common organosilicon material widely used in the rubber and pharmaceutical industries, mainly as a crosslinking agent for room temperature vulcanized silicone rubber, a glass fiber coupling It is used as an end-capping agent for siloxane polymers, and is also one of the important raw materials for the production of silicone resin, benzyl silicone oil, and waterproofing agent.

[0003] At present, the conventional preparation process of methyltrialkoxysilane is to prepare methyltrichlorosilane and ethanol through esterification reaction, and generate hydrogen chloride gas at the same time. However, during the alcoholysis reaction between methyltrichlorosilane and alcohol, the substitution reaction of the third chloro group in methyltrichlorosilane is very difficult, and...

Examples

Embodiment 1

[0032] A. alcoholysis

[0033] 150 parts by weight of methylhydrogendichlorosilane is first vaporized through a vaporizer, and then enters the bottom of the alcoholysis reaction tower through a stripper, and 190 parts by weight of absolute ethanol is added into the alcoholysis reaction tower in liquid form from the top inlet of the alcoholysis reaction tower , the upward gaseous methylhydrogendichlorosilane and the downward liquid anhydrous ethanol are fully contacted, alcoholysis reaction and hydrogen substitution occur, and methyl triethoxysilane and by-product hydrogen chloride are generated; the temperature control of the vaporizer and the stripper All at 55°C; alcoholysis reaction temperature is 45°C;

[0034] Most of the hydrogen chloride escapes through the outlet at the top of the alcoholysis reaction tower, and the remaining hydrogen chloride forms a product mixture with the reaction product;

[0035] B. Neutralization

[0036] Keep the temperature in the stripping ...

Embodiment 2

[0042] Change alcoholysis reaction temperature to be 60 ℃, all the other are the same as embodiment 1.

Embodiment 3

[0044] Change alcoholysis reaction temperature to be 70 ℃, all the other are the same as embodiment 1.

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