阅读说明：本技术 一种有机硅副产盐酸综合回用处理方法 (Comprehensive recycling treatment method for organic silicon byproduct hydrochloric acid ) 是由 王群孝 孟庆曦 谈钱戬 顾玉洪 王勇 薛晓丽 范宝琪 陶波 于 2020-07-08 设计创作，主要内容包括：一种有机硅副产盐酸综合回用处理方法,氯甲烷气化后与硅粉反应生成氯硅烷混合单体,氯硅烷单体进行浓酸水解生成聚甲基硅氧烷以及氯化氢；水解产物经过相分离器后,氯化氢气体进入气体净化冷却系统,甲醇与氯化氢反应生成液相氯甲烷,气液分离器顶部气体进入酸水洗涤塔水洗得到副产稀盐酸送至盐酸储罐；副产稀盐酸静置沉降6-10h后,从罐体底部将副产稀盐酸依次泵至袋式过滤器和衬塑吸附器处理,得到除杂稀盐酸,除杂稀盐酸经亚磷酸二甲酯盐酸回收工序使稀盐酸浓度升高,用于草甘膦的合成工序；本发明的有机硅副产盐酸回用处理方法简单易操作,将稀盐酸经过沉降后,依次经过袋式过滤器和衬塑吸附器处理,实现有机硅副产盐酸和草甘膦原粉的联产操作。(A comprehensive recycling treatment method of organic silicon byproduct hydrochloric acid comprises the steps of gasifying chloromethane, reacting with silicon powder to generate a chlorosilane mixed monomer, and carrying out concentrated acid hydrolysis on the chlorosilane mixed monomer to generate polymethylsiloxane and hydrogen chloride; after the hydrolysate passes through a phase separator, allowing hydrogen chloride gas to enter a gas purification cooling system, allowing methanol and hydrogen chloride to react to generate liquid-phase methyl chloride, allowing gas at the top of the gas-liquid separator to enter an acid water washing tower for washing to obtain a byproduct dilute hydrochloric acid, and conveying the byproduct dilute hydrochloric acid to a hydrochloric acid storage tank; standing and settling the byproduct diluted hydrochloric acid for 6-10h, sequentially pumping the byproduct diluted hydrochloric acid from the bottom of the tank to a bag filter and a plastic-lined adsorber for treatment to obtain impurity-removed diluted hydrochloric acid, and recovering dimethyl phosphite hydrochloric acid from the impurity-removed diluted hydrochloric acid to increase the concentration of the diluted hydrochloric acid for the synthesis process of glyphosate; the recycling treatment method of the organic silicon byproduct hydrochloric acid is simple and easy to operate, and the dilute hydrochloric acid is settled and then sequentially treated by the bag filter and the plastic-lined adsorber, so that the co-production operation of the organic silicon byproduct hydrochloric acid and the glyphosate raw powder is realized.)

1. A comprehensive recycling treatment method of an organic silicon byproduct hydrochloric acid comprises the steps of gasifying liquid-phase chloromethane, reacting the gasified liquid-phase chloromethane with silicon powder in a fluidized bed to generate a chlorosilane mixed monomer, refining and separating out a chlorosilane monomer, and hydrolyzing the chlorosilane monomer by concentrated acid to generate polymethylsiloxane and a byproduct hydrogen chloride; after a hydrolysate passes through a phase separator, hydrogen chloride gas is washed by a washing tower and then enters a gas purification cooling system, methanol reacts with the hydrogen chloride purified by the gas purification cooling system to generate liquid-phase methyl chloride, and gas at the top of a gas-liquid separator enters an acid water washing tower to be washed to obtain by-product dilute hydrochloric acid which is sent to a hydrochloric acid storage tank.

2. The comprehensive recycling treatment method of organosilicon byproduct hydrochloric acid as claimed in claim 1, wherein the plastic-lined adsorber comprises a tank body and a tank cover connected to the tank body via a quick-release flange, a liquid inlet and a liquid outlet are respectively arranged above the tank cover and at the bottom of the tank body, a support orifice plate is connected to the tank body, a filter bag is arranged above the support orifice plate, the edge of the filter bag is connected to the quick-release flange via a clamp, an inner cylinder is arranged inside the filter bag, pretreatment positive pressure adsorption silica gel is filled in the inner cylinder, the adsorption pressure in the tank body is controlled to be 0.05-0.6MPa, and the flow rate of the liquid inlet is 1-3m³/h。

3. The comprehensive recycling treatment method for the byproduct hydrochloric acid of organic silicon according to claim 1, wherein the chlorosilane monomer is dimethyldichlorosilane.

4. The comprehensive recycling treatment method for the byproduct hydrochloric acid of organic silicon as claimed in claim 1, wherein the byproduct dilute hydrochloric acid contains one or more of methyl silanol and organosiloxane.

5. The comprehensive recycling treatment method of the byproduct hydrochloric acid of organic silicon as claimed in claim 1, wherein the byproduct dilute hydrochloric acid contains a characteristic component methanol, and the weight content of methanol is 0.1% -1%.

6. The method as claimed in claim 1, wherein the bag filter is a multi-bag filter, the number of filter bags is 3-5, and the filter bag is a 500-800 mesh nylon filter screen or a glass fiber reinforced plastic filter screen.

7. The comprehensive recycling treatment method for the byproduct hydrochloric acid of organic silicon according to claim 2, wherein the preparation method of the pretreatment positive pressure adsorption silica gel comprises the following steps: soaking the positive pressure adsorption silica gel in nitric acid for 3-5h, then washing the soaked positive pressure adsorption silica gel with steam condensate water until the filtrate is neutral, and putting the obtained positive pressure adsorption silica gel into an oven to be dried for 10-16h to obtain the pretreatment positive pressure adsorption silica gel.

8. The comprehensive recycling treatment method for the byproduct hydrochloric acid of organic silicon according to claim 2, characterized in that a discharge hole is arranged at the bottom of the inner cylinder.

Technical Field

The invention relates to the technical field of organic silicon production, in particular to a comprehensive recycling treatment method for organic silicon byproduct hydrochloric acid.

Background

The hydrogen chloride gas separated out by the hydrolysis of the concentrated organic silicon acid contains siloxane, and the traditional hydrogen chloride purification process comprises the following steps: after hydrolysis reaction, feeding the reaction material into a phase separator to separate the generated hydrogen chloride gas, then passing the hydrogen chloride gas through a gas purification cooling system to obtain purified hydrogen chloride, and then feeding the purified hydrogen chloride to a chloromethane synthesis process; meanwhile, after long-term use, the efficiency of a purification cooling system is difficult to match and purify, so that the entrainment of siloxane in hydrogen chloride gas synthesized by methyl chloride is greatly increased, the siloxane is very unstable in an acid medium, condensation reaction is easy to occur among hydroxyl groups, the molar mass and the gap of the polysiloxane are continuously increased to generate a wall sticking phenomenon, and the siloxane participating in subsequent reaction tends to influence the quality of the methyl chloride; in addition, a large amount of concentrated hydrochloric acid (the concentration is 30%) is needed in the production of glyphosate by the alkyl phosphite process, so that the byproduct dilute hydrochloric acid obtained by washing in a washing tower can be used for synthesizing glyphosate after concentration; siloxane impurities carried in the byproduct hydrochloric acid can affect the quality of the final product glyphosate raw powder.

Disclosure of Invention

The invention aims to solve the defects of the prior art and provides a comprehensive recycling treatment method for the byproduct hydrochloric acid of the organic silicon, wherein liquid-phase chloromethane is gasified and then reacts with silicon powder in a fluidized bed to generate a chlorosilane mixed monomer, the chlorosilane mixed monomer is refined and separated out, and the chlorosilane monomer is subjected to concentrated acid hydrolysis to generate polymethylsiloxane and a byproduct hydrogen chloride; after a hydrolysate passes through a phase separator, hydrogen chloride gas is washed by a washing tower and then enters a gas purification cooling system, methanol reacts with the hydrogen chloride purified by the gas purification cooling system to generate liquid-phase methyl chloride, gas at the top of a gas-liquid separator enters an acid water washing tower to be washed to obtain a byproduct dilute hydrochloric acid, the byproduct dilute hydrochloric acid is sent to a hydrochloric acid storage tank, the byproduct dilute hydrochloric acid is stood and settled in the hydrochloric acid storage tank for 6 to 10 hours, the byproduct dilute hydrochloric acid is sequentially pumped to a bag filter and a plastic-lined adsorber from the bottom of the tank body to be treated to obtain impurity-removed dilute hydrochloric acid, and the concentration of the dilute hydrochloric acid is increased by a dimethyl phosphite hydrochloric acid recovery process for the synthesis process.

The alkyl phosphite process glyphosate production needs a large amount of concentrated hydrochloric acid (the mass concentration is 30 percent) (2.5-4.5 tons/ton), while the production of organosilicon monomers and dimethyl phosphite generates a large amount of hydrochloric acid (the mass concentration is 20-36.5 percent), and impurities contained in the byproduct hydrochloric acid of dimethyl phosphite are mainly phosphorous acid, methanol and methyl chloride, and the impurities are all contained in a glyphosate synthesis system, so the hydrochloric acid can be directly used for synthesizing glyphosate or concentrated, and the hydrochloric acid recovered from the hydrolysis process of the organosilicon monomers contains polysiloxane and can influence the quality of the final product glyphosate raw powder.

Preferably, the plastic-lined adsorber comprises a tank body and a tank cover connected to the upper part of the tank body through a quick-release flange, wherein a liquid inlet and a liquid outlet are respectively formed in the upper part of the tank cover and the bottom of the tank body, a supporting pore plate is connected to the inner part of the tank body, a filter bag is arranged above the supporting pore plate, the edge of the filter bag is connected with the quick-release flange through a clamp, an inner barrel is arranged on the inner side of the filter bag, pretreatment positive-pressure adsorption silica gel is filled in the inner barrel, and0.05-0.6MPa, and the flow rate of the liquid inlet is 1-3m³/h。

Preferably, the chlorosilane monomer is dimethyldichlorosilane.

Preferably, the by-product dilute hydrochloric acid contains one or more of methyl silanol and organic siloxane.

Preferably, the by-product dilute hydrochloric acid contains a characteristic component methanol, and the weight content of the methanol is 0.1-1%.

Preferably, the bag filter is a multi-bag filter, the number of the filter bags is 3-5, and the filter bag is a 500-800 mesh nylon filter screen or a glass fiber reinforced plastic filter screen.

Preferably, the preparation method of the pretreatment positive pressure adsorption silica gel comprises the following steps: soaking the positive pressure adsorption silica gel in nitric acid for 3-5h, then washing the soaked positive pressure adsorption silica gel with steam condensate water until the filtrate is neutral, and putting the obtained positive pressure adsorption silica gel into an oven to be dried for 10-16h to obtain the pretreatment positive pressure adsorption silica gel.

Preferably, the bottom of the inner cylinder is provided with a discharge hole, so that silica gel with saturated adsorption can be conveniently taken out for activation and regeneration.

Has the advantages that:

the method for recycling and treating the organic silicon byproduct hydrochloric acid is simple and easy to operate, and realizes the co-production operation of the organic silicon byproduct hydrochloric acid and the glyphosate raw powder; the method specifically comprises the steps of sequentially treating dilute hydrochloric acid through a bag filter and a plastic-lined adsorber after the dilute hydrochloric acid is settled, wherein the settlement aims to layer the dilute hydrochloric acid and silica gel (formed by polymerizing siloxane) with density smaller than that of the dilute hydrochloric acid, then performing rough filtration through the bag filter and the adsorption effect of filling the silica gel in the plastic-lined adsorber, removing visible meat eye suspended matters through the rough filtration, prolonging the use period of silica gel adsorption, and reducing subsequent adsorption burden; the positive pressure adsorption silica gel can adsorb siloxane in a plastic-lined adsorber at room temperature and low pressure, and pure dilute hydrochloric acid containing alcohol flows out of the plastic-lined adsorber, so that the aim of reducing the siloxane entrainment in the dilute hydrochloric acid is fulfilled, the product quality is more stable, the content of siloxane (calculated by silicon) in the impurity-removed dilute hydrochloric acid is less than or equal to 5ppm, the aim of purification is fulfilled, the recovery of the dilute hydrochloric acid as the byproduct of organosilicon is recycled to the synthesis process of glyphosate, the continuous operation in production is realized, and the production efficiency is improved.

Drawings

FIG. 1 is a schematic diagram of a plastic-lined adsorber of the present invention.

Detailed Description

For the purpose of enhancing the understanding of the present invention, the present invention will be further described in detail with reference to the following examples and the accompanying drawings, which are only used for explaining the present invention and are not to be construed as limiting the scope of the present invention.