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CN-121990937-A - Preparation method of fatty amide propyl betaine

CN121990937ACN 121990937 ACN121990937 ACN 121990937ACN-121990937-A

Abstract

The invention relates to a preparation method of fatty amide propyl betaine, belonging to the technical field of surfactants. The preparation method comprises the following steps of S1, adding N, N-dimethyl propylene diamine into a starting raw material, carrying out heating reflux reaction to obtain fatty amide propyl dimethylamine, wherein the starting raw material comprises at least one of fatty acid and derivatives thereof, S2, adding water, monochloroacetic acid and sodium hydroxide aqueous solution into the fatty amide propyl dimethylamine, heating to carry out quaternization reaction to obtain a crude product, and S3, hydrolyzing the crude product at 70-100 ℃ under the pressure of 0.1-0.5MPa to obtain the fatty amide propyl betaine. According to the preparation method provided by the invention, other impurities are not required to be introduced for post-treatment, and the prepared fatty amide propyl betaine can effectively hydrolyze residual monochloroacetic acid and dichloroacetic acid, reduce byproducts, remarkably improve the safety of products and has higher application value.

Inventors

  • XIE ZHIKAI
  • LIU ZHENHUA
  • YANG WENLING
  • ZHANG YONG
  • CHEN SHENGHUAN
  • HU WENJIE

Assignees

  • 广州花语精细化工有限公司

Dates

Publication Date
20260508
Application Date
20260107

Claims (10)

  1. 1. The preparation method of the fatty amide propyl betaine is characterized by comprising the following steps of: S1, adding N, N-dimethyl propylene diamine into an initial raw material, and carrying out heating reflux reaction to obtain fatty amide propyl dimethylamine, wherein the initial raw material comprises at least one of fatty acid and derivatives thereof; S2, adding water, monochloroacetic acid and sodium hydroxide aqueous solution into the fatty amide propyl dimethylamine, and heating to carry out quaternization reaction to obtain a crude product; S3, hydrolyzing the crude product at 70-100 ℃ and under the pressure of 0.1-0.5MPa to obtain the fatty amidopropyl betaine.
  2. 2. The method for preparing fatty acid amide propyl betaine according to claim 1, wherein in S1, the carbon chain length of the fatty acid and the derivative thereof is C8-C18.
  3. 3. The process for preparing fatty amidopropyl betaine of claim 1 wherein the molar ratio of starting material to N, N-dimethylpropane diamine in S1 is 1.0 (1.0-1.5).
  4. 4. The method for preparing fatty acid amide propyl betaine according to claim 1, wherein in S1, the reaction temperature of the heating reflux is 150-180 ℃ and the reaction time is 8-12h.
  5. 5. The method for preparing fatty acid amide propyl betaine according to claim 1, wherein in S2, the molar ratio of fatty acid amide propyl dimethylamine, monochloroacetic acid and sodium hydroxide is 1 (1.03-1.10): 1.03-1.10.
  6. 6. The method for preparing fatty acid amide propyl betaine according to claim 1, wherein in S2, the temperature of the quaternization reaction is 80-95 ℃ and the reaction time is 2-6h.
  7. 7. The method for preparing fatty amidopropyl betaine according to claim 1, wherein in S3, the time of hydrolysis is 0.5 to 3 hours.
  8. 8. The method for preparing fatty amidopropyl betaine according to claim 1, wherein in S3, the hydrolysis condition is at a temperature of 90-100 ℃ and a pressure of 0.4-0.5MPa.
  9. 9. The method for preparing fatty amidopropyl betaine according to claim 1, wherein in S1, the fatty amidopropyl dimethylamine is obtained by heating and refluxing and then vacuumizing.
  10. 10. The method for preparing fatty acid amide propyl betaine according to claim 9, wherein in S1, the vacuum degree of the vacuum is less than or equal to-0.095 MPa, and the time of the vacuum is 0.5-1h.

Description

Preparation method of fatty amide propyl betaine Technical Field The invention relates to the technical field of surfactants, in particular to a preparation method of fatty amide propyl betaine. Background Fatty amidopropyl betaines are widely used in a number of industries ‌ ‌, such as personal care, oilfield exploitation ‌, textile printing and dyeing, the food industry, and pesticide adjuvants ‌. In the synthesis process of fatty acid amide propyl betaine, chloroacetic acid is needed, and belongs to extremely toxic substances, has strong irritation and corrosiveness to human bodies, and the standard of light industry stipulates that the residual amount of monochloroacetic acid is not more than 20ppm, and meanwhile, the raw material monochloroacetic acid inevitably contains by-product dichloroacetic acid, which belongs to class 2B carcinogens. However, reducing the molar ratio of chloroacetic acid in the reaction process can lead to the reduction of the conversion rate of the intermediate product, and the national standard requirement is not met. Current methods for reducing monochloroacetic acid mainly include oxidation, electrodialysis, and high temperature, high alkali processes, and there are fewer patents and methods related to reducing dichloroacetic acid. In the existing post-treatment method, different impurities such as sulfite, hydrogen peroxide and the like are inevitably introduced by adopting an oxidation method, the quality of a product is influenced, byproducts of the product are increased, the stability of the quality of the product is not facilitated, the electrodialysis method is excessively high in equipment investment and cost, a large amount of waste water is generated, the production cost and the energy consumption are excessively high, the existing industrial production of fatty amidopropyl betaine is generally carried out in an enamel reaction kettle, harmful substances such as monochloroacetic acid and the like are hydrolyzed at high alkali temperature, the tolerance of enamel materials is easily deteriorated for a long time under the conditions of high temperature and high alkali, and in addition, the products produced under the conditions are easy to have the problems of turbidity and the like of different degrees. Therefore, development of a preparation process of fatty amide propyl betaine with strong practicability is needed, the contents of monochloroacetic acid and dichloroacetic acid in the product are effectively reduced on the premise of not affecting the product quality and not bringing other impurities, and the product with low residual quantity is obtained, so that the product safety is improved, and the industrial requirements are met. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a preparation method of fatty amide propyl betaine. The preparation method provided by the invention can obviously reduce the residual monochloroacetic acid and dichloroacetic acid without introducing other impurities, and obviously improves the safety of products. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: in a first aspect, the present invention provides a method for preparing fatty amidopropyl betaine, comprising the steps of: S1, adding N, N-dimethyl propylene diamine into an initial raw material, and carrying out heating reflux reaction to obtain fatty amide propyl dimethylamine, wherein the initial raw material comprises at least one of fatty acid and derivatives thereof; S2, adding water, monochloroacetic acid and sodium hydroxide aqueous solution into the fatty amide propyl dimethylamine, and heating to carry out quaternization reaction to obtain a crude product; S3, hydrolyzing the crude product at 70-100 ℃ and under the pressure of 0.1-0.5MPa to obtain the fatty amidopropyl betaine. According to the preparation method of the fatty acid amide propyl betaine, provided by the invention, after the quaternization of the fatty acid amide propyl dimethylamine is finished, the specific conditions are controlled to hydrolyze, the pH of the system is not required to be increased by adding excessive liquid alkali to remove monochloroacetic acid, the step of adjusting the pH of the system to be neutral after the hydrolysis is finished is omitted, the introduction and use of extra alkali, acid or other substances in the post-treatment step are avoided, the consumption of the liquid alkali is greatly reduced, and the post-treatment flow is simplified. The invention mainly realizes removal of monochloroacetic acid and dichloroacetic acid in the product on the premise of not influencing the quality of the product, not improving the production cost and not bringing other impurities by adjusting the proper hydrolysis temperature and pressure conditions. When the hydrolysis temperature is too low, the hydrolysis efficiency is low, the system can be used to produce byproducts when the temperatur