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CN-122010806-A - Method for synthesizing high-yield anti-sulfuration reducing agent HTS with low sodium salt content

CN122010806ACN 122010806 ACN122010806 ACN 122010806ACN-122010806-A

Abstract

The invention belongs to the technical field of rubber auxiliary agent synthesis, and relates to a synthesis method of a high-yield anti-vulcanization reducing agent HTS with low sodium salt content. Heating sodium thiosulfate pentahydrate, 1, 6-dichlorohexane, deionized water, methanol and lauryl trimethyl ammonium chloride, reacting to obtain an HTS crude product, adding deionized water, cooling, dropwise adding dibenzylamine, dropwise adding sulfuric acid solution, heating, stirring, reacting, filtering, washing, adding deionized water, dropwise adding sodium hydroxide solution, layering, adding toluene into a water layer, extracting, and vacuum drying an organic layer to obtain an HTS product and recycled toluene. According to the invention, the optimal synthesis time is determined by optimizing the process steps and the reaction parameters, the adding rhythm of dibenzylamine and sulfuric acid is controlled, the sodium chloride content in the product is obviously reduced, and the core problem of exceeding the standard of the salt content in the traditional process is solved. The preparation process is simple and controllable, the fluctuation of the product yield and quality is small, and the method is suitable for industrialized mass production popularization.

Inventors

  • SONG XIAOJU
  • MENG FANHU
  • LIU YUANYUAN
  • LIU HAONAN
  • LIU HAICHEN
  • ZHANG YANG
  • ZHANG SONG
  • LIU FUJUN

Assignees

  • 山东尚舜化工有限公司

Dates

Publication Date
20260512
Application Date
20260202

Claims (5)

  1. 1.A synthesis method of a high-yield anti-sulfuration reducing agent HTS with low sodium salt content is characterized by comprising the following steps: (1) Heating sodium thiosulfate pentahydrate, 1, 6-dichlorohexane, deionized water, methanol and lauryl trimethyl ammonium chloride, and reacting to obtain an HTS crude product; (2) Adding deionized water into the HTS crude product, cooling, then dropwise adding dibenzylamine, and then dropwise adding sulfuric acid solution to carry out salination reaction to obtain salination reaction liquid; (3) Heating up and stirring the salinization reaction liquid for reaction, cooling and suction filtering after the reaction is finished, and washing a filter cake obtained by suction filtering to obtain refined HTS-dibenzylamine salt; (4) Adding deionized water into the purified HTS-dibenzylamine, heating, slowly dropwise adding sodium hydroxide solution, standing for layering after the dropwise adding is finished to obtain a dibenzylamine layer and a water layer, and separating and recycling the dibenzylamine layer; (5) Adding toluene into the water layer, stirring, extracting, standing for layering, taking the organic layer, and vacuum drying to obtain HTS product and recovering toluene.
  2. 2. The method for synthesizing the high-yield anti-sulfidation reducing agent HTS with low sodium salt content, which is characterized in that in the step (1), the mass ratio of sodium thiosulfate pentahydrate, 1, 6-dichlorohexane, deionized water, methanol and lauryl trimethyl ammonium chloride is (60-80): 10-30): 40-60): 30-50: 0.1-1, the reaction temperature is 77-79 ℃ and the reaction time is 12-14h.
  3. 3. The method for synthesizing the high-yield anti-sulfidizing reducing agent HTS with low sodium salt content, which is disclosed in claim 1, is characterized in that the adding amount of deionized water in the step (2) is equal to that of deionized water in the step (1), the mass ratio of deionized water to dibenzylamine to sulfuric acid solution in the step (2) is (40-60): 40-65): 55-70, the mass fraction of the sulfuric acid solution is 18-25%, the dropwise adding time of dibenzylamine is 20-40min, and the dropwise adding time of sulfuric acid solution is 50-80min.
  4. 4. The method for synthesizing the high-yield anti-sulfidizing reducing agent HTS with low sodium salt content according to claim 1, wherein in the step (3), the salinization reaction liquid is heated and stirred at the reaction temperature of 60-80 ℃, the reaction time is 2.5-3.5h, the temperature reduction and suction filtration temperature is 35-55 ℃, and the washing liquid is deionized water.
  5. 5. The method for synthesizing high yield of anti-sulfidation reducing agent HTS with low sodium salt content as claimed in claim 1, wherein the temperature rise after adding deionized water in step (4) is 35-55deg.C, and the pH of water layer is 9.4-9.6.

Description

Method for synthesizing high-yield anti-sulfuration reducing agent HTS with low sodium salt content Technical Field The invention belongs to the technical field of rubber auxiliary agent synthesis, and relates to a synthesis method of a high-yield anti-vulcanization reducing agent HTS with low sodium salt content. Background HTS is an important rubber vulcanization-resistant reducer, can solve the problem of reversion of substances such as natural rubber and the like under long-time vulcanization, and is one of key auxiliary agents for manufacturing high-performance and long-service-life tires (such as radial tires and giant engineering tires) and high-end rubber products. The HTS can be used independently to improve the heat resistance, aging resistance, thiofide reversion resistance and dynamic stability of vulcanized rubber, and can improve the fatigue resistance of rubber and the adhesive strength of tire cord when being used together with NR sulfur accelerator. The traditional HTS synthesis process takes penta-sodium thiosulfate and 1, 6-dichlorohexane as raw materials, and a large amount of sodium chloride as a byproduct is generated by heating in water or a water-alcohol mixed solvent for one-step synthesis. Sodium chloride and target product HTS are easy to dissolve in water and are difficult to separate. The existing separation process mostly adopts ethanol for precipitation separation, has the problems of huge solvent consumption, incomplete separation, low yield and the like, and in addition, the filtering and washing effects are seriously dependent on the operation conditions, so that the purity and sodium salt content between batches are easily unstable. It is difficult to meet the stable demands of industrial production. Disclosure of Invention The invention provides a method for synthesizing a high-yield anti-sulfuration reducing agent HTS with low sodium salt content aiming at the problems existing in the traditional HTS synthesis process. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme: a synthesis method of a high-yield anti-sulfuration reducing agent HTS with low sodium salt content comprises the following steps: (1) Heating sodium thiosulfate pentahydrate, 1, 6-dichlorohexane, deionized water, methanol and lauryl trimethyl ammonium chloride, and reacting to obtain an HTS crude product; (2) Adding deionized water into the HTS crude product, cooling, then dropwise adding dibenzylamine, and then dropwise adding sulfuric acid solution to carry out salination reaction to obtain salination reaction liquid; (3) Heating up and stirring the salinization reaction liquid for reaction, cooling and suction filtering after the reaction is finished, and washing a filter cake obtained by suction filtering to obtain refined HTS-dibenzylamine salt; (4) Adding deionized water into the purified HTS-dibenzylamine, heating, slowly dropwise adding sodium hydroxide solution, standing for layering after the dropwise adding is finished to obtain a dibenzylamine layer and a water layer, and separating and recycling the dibenzylamine layer; (5) Adding toluene into the water layer, stirring, extracting, standing for layering, taking the organic layer, and vacuum drying to obtain HTS product and recovering toluene. Preferably, in the step (1), the mass ratio of the sodium thiosulfate pentahydrate, the 1.6-dichlorohexane, the deionized water, the methanol and the lauryl trimethyl ammonium chloride is (60-80): (10-30): (40-60): (30-50): (0.1-1), the reaction temperature is 77-79 ℃ and the reaction time is 12-14h. Preferably, the deionized water in the step (2) is equal to the deionized water in the step (1), the mass ratio of the deionized water to the dibenzylamine to the sulfuric acid solution in the step (2) is (40-60): 40-65): 55-70, the mass fraction of the sulfuric acid solution is 18-25%, the dropwise adding time of the dibenzylamine is 20-40min, and the dropwise adding time of the sulfuric acid solution is 50-80min. Preferably, in the step (3), the salinization reaction liquid is heated, stirred and reacted at 60-80 ℃, the reaction time is 2.5-3.5h, the temperature is reduced, the suction filtration temperature is 35-55 ℃, and the washing liquid is deionized water. Preferably, in the step (4), deionized water is added, the temperature is raised to 35-55 ℃, and the pH of the water layer is 9.4-9.6. The invention adopts a two-step conversion separation method to prepare the HTS product, sulfuric acid solution is used for protonating dibenzylamine to form salt, sodium hydroxide solution is used for regenerating dibenzylamine and releasing HTS, in the production process, insufficient sulfuric acid can lead to incomplete amine salt generation, excessive sulfuric acid can waste and increase post-treatment burden, insufficient sodium hydroxide can lead to incomplete dibenzylamine regeneration, and excessive sulfuric acid can lead to local degradation or emuls