阅读说明：本技术 一种2-丙烯酰胺基-2-甲基丙磺酸盐的制备方法 (Preparation method of 2-acrylamide-2-methylpropanesulfonate ) 是由 张坤树 林普文 李志军 蒋华锋 于 2018-08-22 设计创作，主要内容包括：本发明提供了一种2-丙烯酰胺基-2-甲基丙磺酸盐的制备方法,包括：混合溶剂的制备、碱液的制备、连续中和反应；所述连续中和反应,将2-丙烯酰胺基-2-甲基丙磺酸溶液和碱液连续混合后进行反应,同时开启冷却水系统,温度为-20-30℃,反应液pH为8-10；优选pH为8.5-9.5；还包括滴加第二阻聚剂,搅拌1小时,调节溶液pH=8.5-9.5,继续搅拌30min；本发明得到的2-丙烯酰胺基-2-甲基丙磺酸盐,产品质量稳定,1年内色度指标稳定,变化为5-10；粘度指标稳定,变化为0.1-0.3mpa.s；纯度指标稳定,变化为0.09-0.13%。(The invention provides a preparation method of 2-acrylamide-2-methylpropanesulfonate, which comprises the following steps: preparing a mixed solvent, preparing alkali liquor, and carrying out continuous neutralization reaction; the continuous neutralization reaction comprises the steps of continuously mixing a 2-acrylamide-2-methylpropanesulfonic acid solution and an alkali liquor, reacting, starting a cooling water system at the same time, controlling the temperature to be-20-30 ℃, and controlling the pH of a reaction solution to be 8-10; preferably the pH is 8.5-9.5; dropwise adding a second polymerization inhibitor, stirring for 1 hour, adjusting the pH of the solution to be 8.5-9.5, and continuously stirring for 30 min; the 2-acrylamide-2-methyl propanesulfonate obtained by the invention has stable product quality, and the color index is stable within 1 year and changes to 5-10; the viscosity index is stable and changes to 0.1-0.3 mpa.s; the purity index is stable and the change is 0.09-0.13%.)

1. A preparation method of 2-acrylamide-2-methyl propane sulfonate is characterized in that,

the preparation method of the 2-acrylamide-2-methyl propane sulfonate comprises the following steps: preparing a mixed solvent, preparing alkali liquor, continuously performing neutralization reaction, and dropwise adding a second polymerization inhibitor.

2. The process for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1, wherein,

the continuous neutralization reaction comprises the steps of continuously mixing the 2-acrylamide-2-methylpropanesulfonic acid solution and the alkali liquor according to a certain flow rate, then reacting, simultaneously starting a cooling water system, controlling the temperature to be-20-30 ℃, and controlling the pH of the reaction liquid to be 8-10.

3. The process for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 2, wherein,

the preparation of the mixed solvent comprises the steps of mixing 2-acrylamide-2-methylpropanesulfonic acid powder, a first polymerization inhibitor and water, and stirring for dissolving.

4. The method for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1 or 2,

in the preparation of the mixed solvent, the adding amount of the first polymerization inhibitor is 20ppm-40ppm of the total amount of the 2-acrylamide-2-methylpropanesulfonic acid powder and the water.

5. The process for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1, wherein,

and dropwise adding a second polymerization inhibitor, stirring for 1 hour after dropwise adding the second polymerization inhibitor, adjusting the pH of the solution to be =8-10, and continuously stirring for 30 min.

6. The process for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1, wherein,

and dropwise adding a second polymerization inhibitor, stirring for 1 hour after dropwise adding the second polymerization inhibitor, adjusting the pH of the solution to be 8.5-9.5, and continuously stirring for 30 min.

7. The method for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1 or 6,

and (3) dropwise adding a second polymerization inhibitor, wherein the adding amount of the second polymerization inhibitor is 54-68ppm in terms of the ratio of the total material amount flowing into the No. 2 reaction kettle.

8. The process for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1, wherein,

the first polymerization inhibitor comprises hydroquinone, p-benzoquinone and p-hydroxyanisole, preferably p-hydroxyanisole.

9. The method for producing 2-acrylamido-2-methylpropanesulfonic acid salt according to claim 1 or 7,

the second polymerization inhibitor comprises hydroquinone, p-benzoquinone and p-hydroxyanisole, preferably p-hydroxyanisole.

10. The method for preparing 2-acrylamido-2-methylpropanesulfonate according to claim 1 or 7, wherein the lye is prepared with a lye concentration of 45%.

Technical Field

The invention belongs to the technical field of compound preparation, relates to 2-acrylamide-2-methyl propanesulfonate, and particularly relates to a preparation method of 2-acrylamide-2-methyl propanesulfonate.

Background

2-Acrylamide-2-methylpropanesulfonic acid (2-Acrylamide-2-methylpropanesulfonic acid) is called AMPS for short in English name, is a multifunctional water-soluble anionic monomer and is a white crystalline solid.

The AMPS has excellent performance due to the fact that the AMPS contains a sulfonic acid group which is strong in anionic property, water-soluble and insensitive to salt, a shielded amide group and an unsaturated double bond. The specific structure of AMPS can also be used to improve the overall performance of water insoluble polymers. Its polymer is excellent functional polymer electrolyte, and can be used as dye fixing agent, flocculant, dispersing agent and thickening agent, and can be extensively used in the fields of chemical fibre, plastics, coating material, surfactant, paper-making, water treatment and oil field chemistry, etc.

The 2-acrylamido-2-methylpropanesulfonic acid is a powdery solid per se, is strongly acidic, and is actually produced

The dust is easy to generate in production and use, and equipment corrosion and environmental pollution are caused. Later, foreign companies develop salt solution products, and the solution products have many advantages compared with solid powder, and firstly, various equipment and environmental problems caused by strong acid powder are solved. And secondly, the liquid product is convenient to use and easy to realize the automatic control of downstream industries. Due to the advantages of the 2-acrylamide-2-methyl propanesulfonate solution product, the application range of the product is wider than that of a powder solid, and the market demands at home and abroad tend to rise year by year.

The 2-acrylamide-2-methyl propane sulfonate solution product is generally prepared by neutralizing an alkaline substance and 2-acrylamide-2-methyl propane sulfonic acid, but the neutralization process has certain technical difficulty, if the preparation process has defects, the prepared 2-acrylamide-2-methyl propane sulfonate solution has poor quality stability, and after the solution is stored for a period of time, the solution is easy to turn yellow, the purity is reduced, the viscosity exceeds the standard and even a large amount of self-polymerization is caused, and the like. The performance of the product can not reach the use standard when the product is light, and the product can not be used when the product is heavy, so that the great loss is caused.

Patent CN201510811857.6 mentions a method for preparing 2-acrylamido-2-methylpropanesulfonate monomers, which focuses on purification of acrylamidoalkylsulfonate and high yield. Patent No. cn201310044319.x mentions a method for preparing solid acrylamidoalkylsulfonic acid salts, which has drawbacks in the design of the salt solution preparation process and which is ultimately prepared as a solid salt product. Thus not only the original purpose of preparing the solution product is violated, but also the problem of the quality stability of the salt solution product is not solved.

Disclosure of Invention

Aiming at the defects, the invention provides a preparation method of 2-acrylamide-2-methylpropanesulfonate, which aims to realize and solve the following purposes and technical problems:

(1) the preparation method of the 2-acrylamide-2-methyl propanesulfonate has high efficiency and is easy for large-scale production.

(2) The preparation method of the 2-acrylamide-2-methylpropanesulfonate solves the problems of unstable quality, such as easy yellowing, low purity, over-standard viscosity and even self-polymerization of products prepared by the prior art.

In order to solve the technical problems, the following technical scheme is adopted:

a preparation method of 2-acrylamide-2-methyl propane sulfonate is characterized in that,

the preparation method of the 2-acrylamide-2-methyl propane sulfonate comprises the following steps: preparing a mixed solvent, preparing alkali liquor, continuously performing neutralization reaction, and dropwise adding a second polymerization inhibitor.

As the preferable technical scheme of the invention, the continuous neutralization reaction is carried out by continuously mixing the 2-acrylamide-2-methylpropanesulfonic acid solution and the alkali liquor at a certain flow rate, then reacting, simultaneously starting a cooling water system, controlling the temperature to be-20-30 ℃, and controlling the pH of the reaction solution to be 8-10.

In a preferred embodiment of the present invention, the mixed solvent is prepared by mixing 2-acrylamido-2-methylpropanesulfonic acid powder, a first polymerization inhibitor and water, and stirring and dissolving.

In the preferred embodiment of the present invention, in the preparation of the mixed solvent, the amount of the first polymerization inhibitor added is 20ppm to 40ppm of the total amount of the 2-acrylamido-2-methylpropanesulfonic acid powder and water.

According to a preferable technical scheme of the invention, the second polymerization inhibitor is dropwise added, then stirring is carried out for 1 hour, the pH =8-10 of the solution is adjusted, and stirring is continued for 30 min.

According to a preferable technical scheme of the invention, the second polymerization inhibitor is dropwise added, then stirring is carried out for 1 hour, the pH =8.5-9.5 of the solution is adjusted, and stirring is continued for 30 min.

As a preferable technical scheme of the invention, the second polymerization inhibitor is dripped, and the addition amount of the second polymerization inhibitor is 54-68ppm in terms of the ratio of the total material amount flowing into the No. 2 reaction kettle.

In a preferred embodiment of the present invention, the first polymerization inhibitor includes hydroquinone, p-benzoquinone, and p-hydroxyanisole, preferably p-hydroxyanisole.

In a preferred embodiment of the present invention, the second polymerization inhibitor includes hydroquinone, p-benzoquinone, and p-hydroxyanisole, preferably p-hydroxyanisole.

As a preferable technical scheme of the invention, the preparation of the alkali liquor has the concentration of 45 percent.

The invention provides a preparation method of 2-acrylamide-2-methylpropanesulfonate, which comprises the following steps:

(1) preparation of a mixed solvent: 2-acrylamide-2-methylpropanesulfonic acid powder, a first polymerization inhibitor and water are added into a 2-acrylamide-2-methylpropanesulfonic acid preparation tank, a 2-acrylamide-2-methylpropanesulfonic acid solution with a certain concentration is prepared, and the solution is injected into a head tank 1 for later use.

(2) Preparing alkali liquor: adding an alkaline reagent and water into an alkaline solution preparation tank filled with cooling water, preparing an alkaline solution with a certain concentration, and pumping the alkaline solution into the elevated tank 2 for later use.

(3) Continuous neutralization reaction: and opening valves of the elevated tank 1 and the elevated tank 2, adjusting the flow meter to continuously mix the mixture into the reaction kettle 1 at a certain flow rate for reaction, and simultaneously starting a cooling water system, controlling the temperature to be-20-30 ℃, and controlling the pH of the reaction liquid in the kettle to be always kept at 8-10.

(4) And (3) dropwise adding a second polymerization inhibitor: the mixed liquid obtained in the reaction kettle 1 overflows into the reaction kettle 2, and a certain amount of second polymerization inhibitor solution is dripped at the same time. After stirring for 1h, readjusting the pH value, and stirring for 30min after the adjustment is finished.

(5) And (3) filtering: filtering the reaction solution by a bag filter, directly discharging and packaging. To obtain the 2-acrylamide-2-methyl propane sulfonate.

The weight ratio of the 2-acrylamido-2-methylpropanesulfonic acid powder to water in the step (1) is (1.2-1.5) to 1, preferably 1.3: 1; the adding mode is to add the 2-acrylamide-2-methylpropanesulfonic acid into water.

The inventor of the invention finds in research that the quality stability of the 2-acrylamido-2-methylpropanesulfonic acid salt solution product is not only related to the purity of the 2-acrylamido-2-methylpropanesulfonic acid product, but more importantly to the control of the preparation process of the salt solution. The preparation of the 2-acrylamide-2-methyl propanesulfonate needs to comprehensively consider the control of each link to obtain the 2-acrylamide-2-methyl propanesulfonate product with stable quality, wherein the stability of instantaneous heat release of neutralization reaction and the control of pH are particularly important.

The preparation method of the 2-acrylamide-2-methylpropanesulfonic acid salt comprises the steps of preparing 2-acrylamide-2-methylpropanesulfonic acid powder from a 2-acrylamide-2-methylpropanesulfonic acid synthetic product and a 2-acrylamide-2-methylpropanesulfonic acid refined product, preferably from the 2-acrylamide-2-methylpropanesulfonic acid refined product, wherein the purity is more than or equal to 99 percent, and the iron content is less than or equal to 2 ppm. The inventor researches and finds that the quality stability of the 2-acrylamido-2-methylpropanesulfonic acid salt is greatly influenced by the presence of iron ions, the iron ions can cause slow polymerization of the solution, and the product of the salt solution can gradually turn yellow and deepen the color.

According to the preparation method of the 2-acrylamide-2-methylpropanesulfonate, the alkaline reagent is preferably ionic membrane liquid alkali, impurities are few, and particularly the content of iron ions is low.

The alkali liquor preparation tank needs to be filled with cooling water for cooling, and a large amount of heat can be released in the mixing moment of the alkali liquor and the water, so that the alkali liquor is cooled to normal temperature before neutralization reaction, and the influence of heat release of the neutralization reaction is greatly reduced.

The preparation method of the 2-acrylamide-2-methyl propanesulfonate, disclosed by the invention, has the advantage that the control of the neutralization reaction in the step (3) is a key point. Acid-base neutralization is typically an exothermic reaction, and temperature control is important to control the temperature to-20-30 deg.C, preferably 10-30 deg.C. The temperature is too low, the reaction is too slow, and the time required for the pH value to reach the stationary phase is too long. The temperature is too high and there is a risk of polymerization at any time. It is particularly important to control the pH in the reaction vessel 1 so that it is always maintained at 8 to 10, preferably 8.5 to 9.5, and 2-acrylamido-2-methylpropanesulfonic acid is extremely easily polymerized when the pH is too low, and 2-acrylamido-2-methylpropanesulfonic acid is easily decomposed when the pH is too high, resulting in a decrease in purity. The method is mainly characterized in that the dropping rate of two elevated tank solutions is regulated and controlled, so that two raw materials are maintained at a chemical reaction equilibrium point, and the stability and uniformity of reaction heat release and the stability of pH are powerfully guaranteed.

Drawings

FIG. 1: the device of the invention is schematically connected.

Detailed Description

Embodiments of the present invention are described below with reference to specific examples.