阅读说明：本技术 一种环氧氯丙烷的生产方法 (Production method of epichlorohydrin ) 是由 马东兴 吴迪 张萌 刘�东 于 2019-10-16 设计创作，主要内容包括：本发明公开了一种环氧氯丙烷的生产方法,包括以下步骤：(1)在预反应器中,环氧化催化剂在活化剂的存在下进行预处理,得到预处理催化剂；(2)在反应器内,预处理催化剂催化氯丙烯与过氧化氢发生环氧化反应；(3)将反应液进行油水分离,含催化剂水相经过膜过滤、浓缩,回收催化剂；(4)将油相先进行膜过滤,去除其中的固体物质,过滤清液进行产品精制,得到环氧氯丙烷。本发明通过对催化剂进行预处理,调节了催化剂活性,使生产系统更稳定,过氧化氢有效利用率提高；过氧化氢的无效分解率极低,无繁琐的气相脱氧工序及设备；采用高精度的膜过滤装置,使过滤清液的浊度低,为后续分离工作提供了便利。(The invention discloses a production method of epichlorohydrin, which comprises the following steps: (1) in a pre-reactor, pre-treating an epoxidation catalyst in the presence of an activator to obtain a pre-treated catalyst; (2) in a reactor, catalyzing chloropropene and hydrogen peroxide to perform epoxidation reaction by using a pretreatment catalyst; (3) carrying out oil-water separation on the reaction liquid, filtering and concentrating the catalyst-containing water phase by a membrane, and recovering the catalyst; (4) and (3) performing membrane filtration on the oil phase to remove solid matters in the oil phase, and performing product refining on the filtered clear liquid to obtain the epichlorohydrin. According to the invention, the catalyst is pretreated, so that the activity of the catalyst is regulated, the production system is more stable, and the effective utilization rate of hydrogen peroxide is improved; the ineffective decomposition rate of the hydrogen peroxide is extremely low, and no complicated gas phase deoxidation procedure and equipment are needed; and a high-precision membrane filtering device is adopted, so that the turbidity of the filtered clear liquid is low, and convenience is provided for subsequent separation work.)

1. A production method of epichlorohydrin is characterized by comprising the following steps:

(1) pretreatment of a catalyst: in a pre-reactor, pre-treating an epoxidation catalyst in the presence of an activator to obtain a pre-treated catalyst;

(2) reaction:

in a reactor, catalyzing chloropropene and hydrogen peroxide to perform epoxidation reaction by using a pretreatment catalyst to generate epichlorohydrin and water;

(3) separation:

carrying out oil-water separation on reaction liquid obtained from the reaction system, filtering and concentrating a catalyst-containing water phase by a membrane, and recovering the catalyst;

(4) refining:

and (3) performing membrane filtration on an oil phase obtained after oil-water separation of reaction liquid obtained from the reaction system to remove solid substances in the oil phase, and performing product refining on a filtered clear liquid to obtain the epichlorohydrin.

2. The process for producing epichlorohydrin according to claim 1 wherein the epoxidation catalyst is a liquid, solid or solid-liquid mixed epoxidation catalyst.

3. The epichlorohydrin production method according to claim 1, wherein in the step (1), the activating agent is one or more of methanol, acetonitrile, an organic peroxide, an inorganic peroxide, ammonia water, liquid ammonia, an organic base and an inorganic base.

4. The process for producing epichlorohydrin according to claim 3 wherein the activator is at least one of hydrogen peroxide, ammonia water, liquid ammonia, and an organic base.

5. The process for manufacturing epichlorohydrin according to claim 1, wherein in the step (1), the pretreatment is carried out under conditions of a temperature of 10 ~ 85 ℃, a pressure of ~ 0.5.5 mPa under normal pressure, a pH of 1 ~ 10, and a treatment time of 1 ~ 180 min.

6. The process for manufacturing epichlorohydrin according to claim 1 wherein the amount of the catalyst used in step (2) is 3 ~ 20% based on the total mass of the reaction system.

7. The process for producing epichlorohydrin according to claim 1 wherein the membrane element used in the membrane filtration in the step (3), the membrane filtration during the concentration, and the membrane filtration in the step (4) is at least one of a ceramic membrane, a metal membrane, an organic membrane, and a filter bag, the filtration is performed by dead-end filtration and/or cross-flow filtration, the membrane element precision is 10 ~ 1000000 nm, and the filtrate turbidity is less than 5 NTU.

8. The process for manufacturing epichlorohydrin according to claim 1, wherein 0 ~ 100% of the catalyst recovered in step (3) is recycled to participate in the epoxidation reaction, and the remainder is subjected to catalyst regeneration.

Technical Field

The invention relates to a preparation method of an organic matter, in particular to a production method of epichlorohydrin.

Background

Epichlorohydrin (ECH) is an organic compound, is an important organic chemical raw material and a fine chemical product, and has wide application. The ECH is mainly used for preparing epoxy resin, the epoxy resin prepared by taking epoxy chloropropane as a raw material has the characteristics of strong cohesiveness, chemical medium corrosion resistance, low shrinkage, good chemical stability, high impact strength, excellent dielectric property and the like, and has wide application in the industries of coatings, adhesives, reinforcing materials, casting materials, electronic laminated products and the like. In addition, the epichlorohydrin can also be used for synthesizing glycerol, nitroglycerin explosive, glass fiber reinforced plastic, electrical insulators, surfactants, medicines, pesticides, coatings, sizing materials, ion exchange resins, plasticizers, (condensed) glycerin derivatives, epichlorohydrin rubber and other products, can be used as solvents of cellulose ester, resins and cellulose ether, can be used for producing chemical stabilizers, chemical dyes, water treatment agents and the like, and has wide application value.

At present, the method for preparing epichlorohydrin mainly comprises a propylene high-temperature chlorination method, an acetate propylene-propylene alcohol method, an acrolein method, a glycerol chlorination method and a chloropropene direct epoxidation method.

The chloropropene direct epoxidation method mostly adopts chloropropene and H under the condition of an epoxidation catalyst₂O₂Epoxidation reaction is carried out to generate epichlorohydrin. In the reaction process, the catalytic performance of the catalyst is unstable, which causes production fluctuation, the effective conversion rate is reduced, the product selectivity is reduced, the subsequent separation cost is increased, and even safety accidents are generated, so that the problem to be solved urgently when epoxy chloropropane is produced by a direct epoxy method is solved.

Disclosure of Invention

The invention aims to provide a production method of epichlorohydrin for overcoming the defects of the prior art, so as to ensure the stable reaction performance of a catalyst, improve the effective utilization rate of hydrogen peroxide, improve the yield, reduce the production cost and ensure the safe and stable operation of the production process.

The purpose of the invention is realized as follows:

a production method of epichlorohydrin comprises the following steps:

(1) pretreatment of a catalyst: in a pre-reactor, pre-treating an epoxidation catalyst in the presence of an activator to obtain a pre-treated catalyst;

(2) reaction:

in a reactor, catalyzing chloropropene and hydrogen peroxide to perform epoxidation reaction by using a pretreatment catalyst to generate epichlorohydrin and water;

(3) separation:

carrying out oil-water separation on reaction liquid obtained from the reaction system, filtering and concentrating a catalyst-containing water phase by a membrane, and recovering the catalyst;

(4) refining:

and (3) performing membrane filtration on an oil phase obtained after oil-water separation of reaction liquid obtained from the reaction system to remove solid substances in the oil phase, and performing product refining on a filtered clear liquid to obtain the epichlorohydrin.

According to the production method of the epichlorohydrin, the epoxidation catalyst can be a liquid, solid or solid-liquid mixed epoxidation catalyst.

The production method of the epichlorohydrin comprises the step (1), wherein the activating agent is one or more of methanol, acetonitrile, organic peroxide, inorganic peroxide, ammonia water, liquid ammonia, organic base and inorganic base.

Preferably, in the method for producing epichlorohydrin of the present invention, the activating agent is at least one of hydrogen peroxide, ammonia water, liquid ammonia, and an organic base.

Further preferably, in the present invention, in step (1), the activating agent is preferably hydrogen peroxide and ammonia water, or hydrogen peroxide and organic base, and the hydrogen peroxide concentration is 1 ~ 75 wt.%, preferably 10 ~ 50 wt.%.

The production method of the epichlorohydrin, disclosed by the invention, comprises the step (1), wherein the pretreatment conditions are that the temperature is 10 ~ 85 ℃, the pressure (gauge pressure) is normal pressure ~ 0.5 mPa, the pH value is 1 ~ 10, and the treatment time is 1 ~ 180 min.

Further, in the present invention, the pretreatment temperature is preferably 30 ~ 60 ℃, the pressure (gauge pressure) is ~ 0.5.5 mPa under normal pressure, the pH is preferably 1 ~ 6, the pretreatment time is preferably 10 ~ 60 min, and the catalyst concentration in the pretreatment system is 1 ~ 70 wt.%.

According to the production method of the epichlorohydrin, the mass of the catalyst in the step (2) accounts for 3 ~ 20% of the total mass of the reaction system.

The production method of the epichlorohydrin comprises the steps of (1) membrane filtration in the step (3), membrane filtration in the concentration process and membrane filtration in the step (4) by using at least one of a ceramic membrane, a metal membrane, an organic membrane or a filter bag, wherein the filtration mode is dead-end filtration and/or cross-flow filtration, the membrane element precision is 10 ~ 1000000 nm, and the turbidity of the filtrate is less than 5 NTU.

Further, in the present invention, in the steps (3) and (4), the turbidity of the filtrate is preferably less than 1 NTU.

According to the production method of the epichlorohydrin, 0 ~ 100% of the catalyst recovered in the step (3) is recycled to participate in epoxidation, and the rest is subjected to catalyst regeneration.

The technical scheme of the invention provides a novel process flow for preparing epoxy chloropropane, and the method 1. the catalyst activity is adjusted by pretreating the catalyst, so that a production system is more stable, the effective utilization rate of hydrogen peroxide is improved, the selectivity is improved, the operation cost is reduced, and the system safety is improved; 2. the method has the advantages of extremely low ineffective decomposition rate of the hydrogen peroxide, no complicated gas phase deoxidation procedure and equipment, short process flow and low equipment investment; 3. the invention adopts a high-precision membrane filtering device, so that the turbidity of the filtered clear liquid is low, convenience is provided for subsequent separation work, and the yield of the product is improved; 4. the epoxidation catalyst is pretreated, and a part of the catalyst is concentrated and recycled, so that the activity of the catalyst is effectively adjusted, the production stability is ensured, the energy consumption is reduced, and the catalyst has a good market application prospect.

Drawings

FIG. 1 is a schematic process flow diagram of the present invention.

Detailed Description

The technical solution of the present invention is further described below with reference to fig. 1 by specific examples, but the technical solution of the present invention is not limited thereto.