CN109867587B - Preparation method of 3-chloro-1,2-propanediol - Google Patents

Abstract

The invention provides a preparation method of 3 chloro-1,2-propanediol, which takes hydrogen peroxide as an oxygen source, controls a reaction phase transfer catalyst to catalyze chloropropene to generate epichlorohydrin, and then prepares the 3 chloro-1,2-propanediol by hydrolysis, wherein the preparation process mainly comprises three steps of epoxidation, hydrolysis and product purification to obtain the product 3 chloro-1,2-propanediol with the content of more than 99.9 percent.

Description

Preparation method of 3-chloro-1,2-propanediol

Technical Field

The invention belongs to the field of petrochemical industry, and particularly relates to a preparation method of 3-chloro-1, 2-propanediol.

Background

3-chloro-1,2-propanediol (3-chloro-1,2-propanediol), commonly known as 3-chloro-1, 2-dihydroxypropane, having the molecular formula C₃H₇CIO₂And the molecular weight is 110.55. Can be used as an organic synthesis intermediate to synthesize pesticides, medicines, coatings, plasticizers, surfactants and the like; at present, the synthesis of 3-chloro-1,2-propanediol mainly comprises an epichlorohydrin hydrolysis method and a glycerol chlorination method.

The glycerol chlorination method is to add glycerol and acetic acid into a reaction kettle, stir and heat the mixture to 90-95 ℃, introduce dry hydrogen chloride gas until the weight of the reaction liquid is increased to 150% (theoretical value), and the end point is obtained. And carrying out reduced pressure distillation to obtain a crude product. Then the 3-chloro-1,2-propanediol is obtained by collecting the 128-phase 132 ℃ (1.33-2.67kPa) fraction. The glycerol method has the disadvantages that more byproducts are produced, the content and purity of the product are difficult to reach more than 99.5 percent, and hydrogen chloride gas has high requirements on equipment and large investment.

The epoxy chloropropane hydrolysis method is to add epoxy chloropropane into a reaction pot, stir, add dilute sulphuric acid to make the reaction solution acidic, heat up, reflux for 1h, and rectify the obtained product under reduced pressure to obtain the finished product. Although the epichlorohydrin hydrolysis method is a mature method at home and abroad, the defects are that the traditional chlorohydrin method production of raw material epichlorohydrin is difficult to meet the national requirements of energy conservation, emission reduction and environmental protection, in addition, organic acid is used as a catalyst, side reaction is generated to reduce the yield, and the subsequent process is easily affected by the addition of alkali to adjust the pH value, so that the process parameters are difficult to adjust and control, the solid waste is increased, and the like.

CN201010011544.X discloses a production method of high-purity 3-chloro-1,2-propanediol, which comprises the following steps: (1) respectively dissolving sulfuric acid, benzenesulfonic acid and succinic acid in deionized water to prepare a sulfuric acid solution, a benzenesulfonic acid solution and a succinic acid solution; (2) mixing and reacting part of sulfuric acid solution, part of benzenesulfonic acid solution and part of epichlorohydrin for a period of time, raising the temperature, adding the rest of epichlorohydrin, sequentially adding the rest of benzenesulfonic acid solution and sulfuric acid solution in different periods of time, adding succinic acid solution at one time, and raising the temperature to continue reacting; (3) after the hydrolysis reaction is finished, adding an alkali solution, and stirring to ensure that the reaction is uniform; (4) dehydrating the hydrolysate after the alkali is added, adding the alkali solution after the dehydration, and heating under the stirring condition; (5) heating the material under vacuum condition, transferring into a distillation system, and distilling to obtain the product 3-chloro-1,2-propanediol when the vacuum degree is more than or equal to 0.1 MPa. The method has the defects that in the hydrolysis process of the epichlorohydrin, organic acid is used as a catalyst, side reaction can occur until the yield is reduced, and the addition of alkali after the hydrolysis reaction is finished to adjust the pH value easily causes adverse effects such as difficult adjustment and control of process parameters, increase of solid wastes and the like on a subsequent process.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the defects of the existing 3-chloro-1,2-propanediol production technology, the preparation method of the 3-chloro-1,2-propanediol with few byproducts, simple, green and environment-friendly process and high product purity is provided.

In order to solve the technical problems, the technical scheme of the invention is as follows:

the method takes hydrogen peroxide as an oxygen source, controls a reaction and controls a phase transfer catalyst to catalyze chloropropene to generate epichlorohydrin, and then prepares the 3-chloro-1,2-propanediol by hydrolysis. The preparation process mainly comprises the following three steps of epoxidation reaction, hydrolysis reaction and product purification:

epoxidation reaction: in the presence of a reaction control phase transfer catalyst, performing chloropropene epoxidation reaction to prepare epoxy chloropropane, wherein the molar ratio of chloropropene to hydrogen peroxide is 1.5-4.5: 1; the reaction temperature is

40-65 ℃; the reaction time is 2-6 h; the reaction pressure is 0.1-1 MPa; the hydrogen peroxide is a hydrogen peroxide solution with the mass concentration of 15-50%.

And (3) hydrolysis reaction: continuously adding hydrogen peroxide, deionized water and a solid acid catalyst into the obtained epoxidation reaction material for reaction, wherein the molar ratio of the epoxidation product epoxy chloropropane to the hydrogen peroxide is 1.5-4.5: 1; the mol ratio of epoxy chloropropane of an epoxidation product to deionized water is 0.5-1.5: 1, and the reaction temperature is 45-95 ℃; the reaction time is 2-4 h; the reaction pressure is 0.1-1.5 MPa.

And (3) product purification: washing the hydrolysis reaction material by chloropropene, and then carrying out reduced pressure distillation to remove chloropropene, water and epichlorohydrin in the reaction liquid to obtain the product 3 chloro-1, 2-propanediol. The adding mass of the washing chloropropene is 0.5-2 times of that of the solid acid catalyst hydrolysis reaction material separated by filtering, the vacuum degree of reduced pressure distillation is 1000-200 KPa, and the temperature of reduced pressure distillation is 65-120 ℃.

Separating the reaction control phase transfer catalyst from reaction liquid after the epoxidation reaction of generating epoxy chloropropane by catalyzing chloropropene by the reaction control phase transfer catalyst, and recycling the reaction control phase transfer catalyst for the epoxidation reaction; the reaction-controlled phase transfer catalyst is [ pi-C₅H₅NC₁₆H₃₃]₃(PO₄)(WO₃)₄]。

The solid acid catalyst used in the hydrolysis reaction is commercial SiO₂-Al₂O₃Or B₂O₃-Al₂O₃One or two, if two, SiO₂-Al₂O₃And B₂O₃-Al₂O₃The mass ratio is 0.5-2: 1.

The product purification hydrolysis reaction material is a solid acid catalyst reaction material which is obtained by filtering and separating after the hydrolysis reaction is finished, and the solid acid catalyst is recycled for the hydrolysis reaction.

By adopting the technical scheme, the invention has the beneficial effects that:

1. hydrogen peroxide is used as an oxygen source, and a phase transfer catalyst is controlled to react to catalyze chloropropene to generate epichlorohydrin, so that the pollution influence of the traditional chlorohydrin method production process of epichlorohydrin is overcome, and the requirements of energy conservation, emission reduction and environmental protection advocated by the state are met;

2. the solid acid catalyst is used for replacing inorganic acid, carboxylic acid or benzene sulfonic acid for hydrolysis of epoxy chloropropane, so that the conversion rate of epoxy chloropropane is improved, hydrolysis by-products are reduced, waste acid discharge is reduced, and the solid acid catalyst can be recycled.

3. Alkali is not needed to be added for adjusting the pH value, the production process is simplified, and the solid waste discharge is reduced.

4. The purity of the obtained 3-chloro-1,2-propanediol product is more than or equal to 99.9 percent.

Detailed Description

The invention is further illustrated below with reference to specific examples.

Example 1

300g of chloropropene and 90g of 50% aqueous hydrogen peroxide solution are added into a 1000ml reaction kettle, and 20g of reaction control phase transfer catalyst [ pi-C ] is added₅H₅NC₁₆H₃₃]₃(PO₄)(WO₃)₄]The reaction temperature is 45 ℃, the reaction pressure is 0.5MPa, and after 2.5 hours of reaction, the reaction materials are centrifugally separated and recovered to control the phase transfer catalyst.

Continuously adding 90g of aqueous solution of hydrogen peroxide with the mass concentration of 50%, 400g of deionized water and a solid acid catalyst B into the material containing the epoxy chloropropane₂O₃-Al₂O₃5g of the mixture is reacted for 2 hours at the temperature of 75 ℃, and the reaction pressure is 1.5 MPa.

And after the hydrolysis reaction is finished, filtering and separating out solid acid catalyst reaction materials, washing the filtrate by 300g of chloropropene, and then carrying out reduced pressure distillation, wherein the vacuum degree of the reduced pressure distillation is 400KPa, the reduced pressure distillation temperature is 110 ℃, 290g of 3-chloro-1,2-propanediol product is obtained, the chroma of the product is less than or equal to 15, the purity of the product is 99.97% by GC analysis, the low-boiling content is less than or equal to 0.01%, the high-boiling content is less than or equal to 0.02%, and the moisture is less than or equal to 300 ppm.

Example 2

300g of chloropropene and 90g of 50% aqueous hydrogen peroxide solution are added into a 1000ml reaction kettle, and 20g of reaction control phase transfer catalyst [ pi-C ] is added₅H₅NC₁₆H₃₃]₃(PO₄)(WO₃)₄]The reaction temperature is 45 ℃, the reaction pressure is 0.5MPa, and after 2.5 hours of reaction, the reaction materials are centrifugally separated and recovered to control the phase transfer catalyst.

The preparation method comprises the steps ofAdding 120g of 50% hydrogen peroxide aqueous solution, 300g of deionized water and a solid acid catalyst SiO into the alkane material₂-Al₂O₃5g of the mixture is reacted for 1.5h at the temperature of 75 ℃, and the reaction pressure is 1.0 MPa.

And filtering and separating solid acid catalyst reaction materials after the hydrolysis reaction is finished, washing the filtrate by 350g of chloropropene, and then carrying out reduced pressure distillation, wherein the vacuum degree of the reduced pressure distillation is 200KPa, the reduced pressure distillation temperature is 120 ℃, 320g of 3-chloro-1,2-propanediol product is obtained, the chroma of the product is less than or equal to 15, the purity of the product is 99.98 percent by GC analysis, the low-boiling content is 0.00 percent, the high-boiling content is less than or equal to 0.02 percent, and the moisture is less than or equal to 200 ppm.

Claims (3)

1. A preparation method of 3-chloro-1,2-propanediol is characterized by comprising the following steps: hydrogen peroxide is used as an oxygen source, a phase transfer catalyst is controlled in reaction to catalyze chloropropene to generate epoxy chloropropane, and 3-chloro-1,2-propanediol is prepared by hydrolysis;

the preparation process comprises the following steps:

(1) epoxidation reaction: in the presence of a reaction control phase transfer catalyst, performing epoxidation reaction on chloropropene and hydrogen peroxide to prepare epoxy chloropropane, wherein the molar ratio of chloropropene to hydrogen peroxide is 1.5-4.5: 1; the reaction temperature is 40-65 ℃; the reaction time is 2-6 h; the reaction pressure is 0.1-1 MPa; the hydrogen peroxide is a hydrogen peroxide solution with the mass concentration of 15-50%;

(2) and (3) hydrolysis reaction: continuously adding hydrogen peroxide, deionized water and a solid acid catalyst into the obtained epoxidation reaction material for reaction, wherein the molar ratio of the epoxidation product epoxy chloropropane to the hydrogen peroxide is 1.5-4.5: 1; the mol ratio of epoxy chloropropane of an epoxidation product to deionized water is 0.5-1.5: 1, and the reaction temperature is 45-95 ℃; the reaction time is 2-4 h; the reaction pressure is 0.1-1.5 MPa;

(3) and (3) product purification: washing the hydrolysis reaction material by using chloropropene, and then carrying out reduced pressure distillation to remove chloropropene, water and epoxy chloropropane in the reaction liquid to obtain a product 3-chloro-1, 2-propanediol; adding 0.5-2 times of washing chloropropene in mass of the solid acid catalyst hydrolysis reaction material separated by filtering, performing reduced pressure distillation at a vacuum degree of 1000-200 KPa and a reduced pressure distillation temperature of 65-120 ℃,

wherein the reaction in the step (1) controls the phase transfer catalyst to be [ pi-C₅H₅NC₁₆H₃₃]₃(PO₄)(WO₃)₄]，

The solid acid catalyst used in the hydrolysis reaction in the step (2) is SiO₂-Al₂O₃Or B₂O₃-Al₂O₃One or two, if two, SiO₂-Al₂O₃And B₂O₃-Al₂O₃The mass ratio is 0.5-2: 1.

2. The method of claim 1, wherein:

and separating the reaction control phase transfer catalyst from reaction liquid after the epoxidation reaction of generating epoxy chloropropane by catalyzing chloropropene by the reaction control phase transfer catalyst, wherein the reaction control phase transfer catalyst is recycled for the epoxidation reaction.

3. The method of claim 1, wherein:

the product purification hydrolysis reaction material is a solid acid catalyst reaction material which is obtained by filtering and separating after the hydrolysis reaction is finished, and the solid acid catalyst is recycled for the hydrolysis reaction.