阅读说明：本技术 一种甲基丙烯酸钠的连续化生产工艺及其设备 (Continuous production process and equipment for sodium methacrylate ) 是由 李善龙 钱庆安 汪青海 陈新建 刘亚婷 张云岩 张海卫 张旭辉 于 2020-08-21 设计创作，主要内容包括：本发明提供了一种甲基丙烯酸钠的连续化生产工艺及其设备,属于化工材料制备技术领域。本发明将甲基丙烯酸和氢氧化钠加入到连续化生产设备中,实现了甲基丙烯酸钠的连续化生产。通过本发明,不但实现了甲基丙烯酸钠的连续化生产,而且极大的提高了生产效率,使耗时较长的反应能够在短时间内完成。而且,通过本发明所生产的甲基丙烯酸钠中聚甲基丙烯酸钠的含量显著降低,且产品的铂钴色度降低至5以内。(The invention provides a continuous production process and continuous production equipment for sodium methacrylate, and belongs to the technical field of chemical material preparation. According to the invention, methacrylic acid and sodium hydroxide are added into continuous production equipment, so that continuous production of sodium methacrylate is realized. The invention not only realizes the continuous production of the sodium methacrylate, but also greatly improves the production efficiency, and ensures that the reaction which takes longer time can be completed in a short time. Moreover, the content of the sodium polymethacrylate in the sodium methacrylate produced by the invention is obviously reduced, and the platinum-cobalt color of the product is reduced to be less than 5.)

1. A continuous production process of sodium methacrylate is characterized by comprising the following steps:

(1) pumping 60% sodium hydroxide solution into a first reaction kettle (1) through a pressure pump, introducing deionized water, and fully stirring to adjust the concentration of sodium hydroxide to be 5-60%;

(2) adding methacrylic acid into a second reaction kettle (2), adding a composite polymerization inhibitor 1, and fully stirring and uniformly mixing;

(3) pumping methacrylic acid containing a composite polymerization inhibitor 1 in a second reaction kettle (2) into a static mixer (3) through a pressure pump, then adding a prepared sodium hydroxide solution in the first reaction kettle (1) into the static mixer (3) for fully mixing, and adding the composite polymerization inhibitor 2; sodium hydroxide: the ratio of methacrylic acid is 1: 0.99;

(4) the mixed liquid is conveyed into a pipeline type reactor (4), the reaction temperature is controlled to be 0-100 ℃ through the flow of jacket chilled water of the pipeline type reactor (4), and the reaction time is 5-30 min;

(5) after the reaction is finished, the reaction solution enters a spray dryer (5) for spray drying to obtain a finished product of sodium methacrylate.

2. The production process according to claim 1, wherein the composite polymerization inhibitor 1 consists of hydroquinone, phenothiazine and ZJ 701; according to the mass ratio, hydroquinone: phenothiazine: ZJ701 is 1: 025: 0.3; the addition amount of the composite polymerization inhibitor 1 is 50-2000 ppm.

3. The production process according to claim 1, wherein the composite polymerization inhibitor 2 is composed of diphenol and phenothiazine; according to the mass ratio, hydroquinone: the phenothiazine accounts for 1: 0.9; the addition amount of the composite polymerization inhibitor 2 was 300 ppm.

4. The process according to claim 1, wherein the spray dryer has a gas phase outlet temperature of 100-140 ℃.

5. The production process according to claim 1, wherein the treatment equipment of the production process comprises a first reaction kettle (1) and a second reaction kettle (2), a feed inlet of the first reaction kettle (1) is connected with a pressure pump, and a water inlet of the first reaction kettle (1) is connected with deionized water;

a feeding hole of the second reaction kettle (2) is connected with a pressure pump, and a filling hole is formed in the top of the second reaction kettle (2) and used for adding a composite polymerization inhibitor 1;

the discharge ports of the first reaction kettle (1) and the second reaction kettle (2) are connected with the feed port of the static mixer (3) through a pipeline, and the top of the static mixer (3) is provided with a filling port for adding the composite polymerization inhibitor 2;

a discharge hole of the static mixer (3) is connected with a feed hole of the tubular reactor (4) through a pipeline, and chilled water is arranged in a jacket of the tubular reactor (4) and used for controlling the reaction temperature;

and a discharge hole of the tubular reactor is connected with a feed inlet of the spray dryer (5) through a pipeline, and the spray dryer dries the sodium methacrylate and discharges waste gas.

6. The production process of the sodium methacrylate is characterized by comprising the following steps:

(1) pumping 60% sodium hydroxide solution into a first reaction kettle (1) through a pressure pump, introducing deionized water, and fully stirring to adjust the concentration of sodium hydroxide to 35%;

(2) adding methacrylic acid into a second reaction kettle (2), adding a composite polymerization inhibitor 1, and fully stirring and uniformly mixing; the composite polymerization inhibitor 1 consists of hydroquinone, phenothiazine and ZJ 701; according to the mass ratio, hydroquinone: phenothiazine: ZJ701 is 1: 025:0.3, wherein the addition amount of the composite polymerization inhibitor 1 is 200 ppm;

(3) pumping methacrylic acid containing a composite polymerization inhibitor 1 in the second reaction kettle into a static mixer (3) through a pressure pump, then adding the prepared sodium hydroxide solution in the first reaction kettle (1) into the static mixer (3) for fully mixing, and adding a composite polymerization inhibitor 2; sodium hydroxide: the ratio of methacrylic acid is 1: 0.99; the composite polymerization inhibitor 2 consists of benzenediol and phenothiazine; according to the mass ratio, hydroquinone: the phenothiazine accounts for 1: 0.9; the addition amount of the composite polymerization inhibitor 2 is 300 ppm;

(4) the mixed liquid is conveyed into a pipeline type reactor (4), the reaction temperature is controlled at 50 ℃ through the flow of jacket chilled water of the pipeline type reactor (4), and the reaction time is 15 min;

(5) after the reaction is finished, the reaction solution enters a spray dryer (5) for spray drying to obtain a finished product of sodium methacrylate; the gas phase outlet temperature of the spray dryer is 120 ℃;

the treatment equipment of the production process comprises a first reaction kettle (1) and a second reaction kettle (2), wherein a feed inlet of the first reaction kettle (1) is connected with a pressure pump, and a water inlet of the first reaction kettle (1) is connected with deionized water;

a feeding hole of the second reaction kettle (2) is connected with a pressure pump, and a filling hole is formed in the top of the second reaction kettle (2) and used for adding a composite polymerization inhibitor 1;

the discharge ports of the first reaction kettle (1) and the second reaction kettle (2) are connected with the feed port of the static mixer (3) through a pipeline, and the top of the static mixer (3) is provided with a filling port for adding the composite polymerization inhibitor 2;

a discharge hole of the static mixer (3) is connected with a feed hole of the tubular reactor (4) through a pipeline, and chilled water is arranged in a jacket of the tubular reactor (4) and used for controlling the reaction temperature;

and a discharge hole of the tubular reactor is connected with a feed inlet of the spray dryer (5) through a pipeline, and the spray dryer dries the sodium methacrylate and discharges waste gas.

7. The equipment for continuous production of the methacrylic acid is characterized by comprising a first reaction kettle (1) and a second reaction kettle (2), wherein a feed inlet of the first reaction kettle (1) is connected with a pressure pump, and a water inlet of the first reaction kettle (1) is connected with deionized water;

a feeding hole of the second reaction kettle (2) is connected with a pressure pump, and a filling hole is formed in the top of the second reaction kettle (2) and used for adding a composite polymerization inhibitor 1;

the discharge ports of the first reaction kettle (1) and the second reaction kettle (2) are connected with the feed port of the static mixer (3) through a pipeline, and the top of the static mixer (3) is provided with a filling port for adding the composite polymerization inhibitor 2;

a discharge hole of the static mixer (3) is connected with a feed hole of the tubular reactor (4) through a pipeline, and chilled water is arranged in a jacket of the tubular reactor (4) and used for controlling the reaction temperature;

the discharge hole of the tubular reactor is connected with the feed inlet of the spray dryer (5) through a pipeline, and the spray dryer (5) dries the sodium methacrylate and discharges waste gas.

Technical Field

The invention relates to the technical field of chemical material preparation, in particular to a continuous production process of sodium methacrylate.

Background

Sodium methacrylate is an important chemical raw material, is a polyanionic polymer dielectric and is an important chemical product with wide application in recent development. The method is widely applied to the departments of environmental protection, food, medicine, textile, water treatment, petrochemical, metallurgy and the like. Meanwhile, sodium (meth) acrylate is also one of the materials for producing sodium polyacrylate, and sodium polyacrylate has various properties due to its different molecular weights and is widely used in the fields of food, feed, textile, paper making, water treatment, petrochemical industry, agriculture, forestry, horticulture, physiological hygiene, and the like. In addition, sodium methacrylate is also a main raw material for producing glycidyl methacrylate, and glycidyl methacrylate has extremely wide application in aspects of organic synthesis, high-molecular synthesis, polymer modification, composite materials, ultraviolet curing materials, coatings, adhesives, leather, chemical fiber paper making, printing and dyeing and the like. The range of applications of sodium methacrylate is becoming more and more extensive, based on its own characteristics and as a main raw material for downstream products.

At present, the production process of sodium methacrylate still adopts the traditional intermittent production process, the process is intermittent feeding and discharging, the production efficiency is low, the operation is inconvenient, the product quality is unstable, and the chromaticity of the product cannot reach less than 20 (platinum-cobalt chromaticity). In addition, the production adopts a material dripping mode, the reaction time is long, the reaction temperature is not accurately controlled, the yield is influenced, and the polymerization tendency is increased. Moreover, the materials are added in the order of adding the acid into the alkali liquor, and double bond polymerization is more easily caused under an alkaline environment. The polymerization inhibitor has a single system, and the polymerization inhibition effect is poor in the material production and storage processes. Therefore, a continuous and efficient operation process is needed.

Disclosure of Invention

The invention aims to provide a continuous production process of sodium methacrylate.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a continuous production process of sodium methacrylate, which comprises the following steps:

(1) pumping 60% sodium hydroxide solution into a first reaction kettle through a pressure pump, introducing deionized water, and fully stirring to adjust the concentration of sodium hydroxide to 5-60%;

(2) adding methacrylic acid into a second reaction kettle, adding a composite polymerization inhibitor 1, and fully stirring and uniformly mixing;

(3) pumping methacrylic acid containing a composite polymerization inhibitor 1 in the second reaction kettle into a static mixer through a pressure pump, then adding the prepared sodium hydroxide solution in the first reaction kettle into the static mixer for fully mixing, and adding a composite polymerization inhibitor 2; sodium hydroxide: the ratio of methacrylic acid was 1: 0.99.

(4) The mixed liquid is conveyed into a pipeline type reactor, the reaction temperature is controlled to be 0-100 ℃ through the flow of jacket chilled water of the pipeline type reactor, and the reaction time is 5-30 min;

(5) and after the reaction is finished, the reaction solution enters a spray dryer for spray drying to obtain a finished product of sodium methacrylate.

Preferably, the composite polymerization inhibitor 1 consists of hydroquinone, phenothiazine and ZJ 701; according to the mass ratio, hydroquinone: phenothiazine: ZJ701 is 1: 025: 0.3; the addition amount of the composite polymerization inhibitor 1 is 50-2000 ppm.

Preferably, the composite polymerization inhibitor 2 consists of benzenediol and phenothiazine; according to the mass ratio, hydroquinone: the phenothiazine accounts for 1: 0.9; the addition amount of the composite polymerization inhibitor 2 was 300 ppm.

Preferably, the gas phase outlet temperature of the spray dryer is 100-140 ℃.

Preferably, the treatment equipment of the production process comprises a first reaction kettle and a second reaction kettle, wherein a feed inlet of the first reaction kettle is connected with a pressure pump, and a water inlet of the first reaction kettle is connected with deionized water;

a feeding hole of the second reaction kettle is connected with a pressure pump, and a filling hole is formed in the top of the second reaction kettle and used for adding a composite polymerization inhibitor 1;

the discharge ports of the first reaction kettle and the second reaction kettle are connected with the feed port of a static mixer through a pipeline, and the top of the static mixer is provided with a filling port for adding a composite polymerization inhibitor 2;

the discharge hole of the static mixer is connected with the feed hole of the tubular reactor through a pipeline, and chilled water is arranged in a jacket of the tubular reactor and used for controlling the reaction temperature;

and the discharge hole of the tubular reactor is connected with the feed inlet of the spray dryer through a pipeline, and the spray dryer dries the sodium methacrylate and discharges waste gas.

In addition, the present invention provides a preferred production process of sodium methacrylate, comprising the steps of:

(1) pumping 60% sodium hydroxide solution into a first reaction kettle through a pressure pump, introducing deionized water, and fully stirring to adjust the concentration of sodium hydroxide to 35%;

(2) adding methacrylic acid into a second reaction kettle, adding a composite polymerization inhibitor 1, and fully stirring and uniformly mixing; the composite polymerization inhibitor 1 consists of hydroquinone, phenothiazine and ZJ 701; according to the mass ratio, hydroquinone: phenothiazine: ZJ701 is 1: 025:0.3, wherein the addition amount of the composite polymerization inhibitor 1 is 200 ppm;

(3) pumping methacrylic acid containing a composite polymerization inhibitor 1 in the second reaction kettle into a static mixer through a pressure pump, then adding the prepared sodium hydroxide solution in the first reaction kettle into the static mixer for fully mixing, and adding a composite polymerization inhibitor 2; sodium hydroxide: the ratio of methacrylic acid is 1: 0.99; the composite polymerization inhibitor 2 consists of benzenediol and phenothiazine; according to the mass ratio, hydroquinone: the phenothiazine accounts for 1: 0.9; the addition amount of the composite polymerization inhibitor 2 is 300 ppm;

(4) the mixed liquid is conveyed into a pipeline type reactor, the reaction temperature is controlled at 50 ℃ through the flow of jacket chilled water of the pipeline type reactor, and the reaction time is 15 min;

(5) after the reaction is finished, the reaction solution enters a spray dryer for spray drying to obtain a finished product of sodium methacrylate; the gas phase outlet temperature of the spray dryer was 120 ℃.

The treatment equipment of the production process comprises a first reaction kettle and a second reaction kettle, wherein a feed inlet of the first reaction kettle is connected with a pressure pump, and a water inlet of the first reaction kettle is connected with deionized water;

a feeding hole of the second reaction kettle is connected with a pressure pump, and a filling hole is formed in the top of the second reaction kettle and used for adding a composite polymerization inhibitor 1;

the discharge ports of the first reaction kettle and the second reaction kettle are connected with the feed port of a static mixer through a pipeline, and the top of the static mixer is provided with a filling port for adding a composite polymerization inhibitor 2;

the discharge hole of the static mixer is connected with the feed hole of the tubular reactor through a pipeline, and chilled water is arranged in a jacket of the tubular reactor and used for controlling the reaction temperature;

and the discharge hole of the tubular reactor is connected with the feed inlet of the spray dryer through a pipeline, and the spray dryer dries the sodium methacrylate and discharges waste gas.

In addition, the invention provides equipment for continuous production of methacrylic acid, which comprises a first reaction kettle and a second reaction kettle, wherein a feed inlet of the first reaction kettle is connected with a pressure pump, and a water inlet of the first reaction kettle is connected with deionized water;

a feeding hole of the second reaction kettle is connected with a pressure pump, and a filling hole is formed in the top of the second reaction kettle and used for adding a composite polymerization inhibitor 1;

the discharge ports of the first reaction kettle and the second reaction kettle are connected with the feed port of a static mixer through a pipeline, and the top of the static mixer is provided with a filling port for adding a composite polymerization inhibitor 2;

the discharge hole of the static mixer is connected with the feed hole of the tubular reactor through a pipeline, and chilled water is arranged in a jacket of the tubular reactor and used for controlling the reaction temperature;

and the discharge hole of the tubular reactor is connected with the feed inlet of the spray dryer through a pipeline, and the spray dryer dries the sodium methacrylate and discharges waste gas.

The invention has the beneficial effects that

The invention not only realizes the continuous production of the sodium methacrylate, but also greatly improves the production efficiency, and ensures that the reaction which takes longer time can be completed in a short time. Moreover, by reasonable collocation and addition of the compound polymerization inhibitor and shortening of the reaction time, the phenomenon of double bond polymerization in the reaction process is effectively reduced, so that the content of the sodium polymethacrylate in the sodium methacrylate produced by the invention is obviously reduced.

Drawings

FIG. 1 is a schematic view of a treating apparatus according to the present invention

1. The first reaction kettle 2, the second reaction kettle 3, the static mixer 4, the pipeline type reactor 5 and the spray dryer.

Detailed Description

The present invention will be further described with reference to the following examples, which are intended to be illustrative only and not to be limiting of the invention in any way, and any person skilled in the art can modify the present invention by applying the teachings disclosed above and applying them to equivalent embodiments with equivalent modifications. Any simple modification or equivalent changes made to the following embodiments according to the technical essence of the present invention, without departing from the technical spirit of the present invention, fall within the scope of the present invention.