Production process of rubber vulcanization accelerator mbts

Abstract

The invention belongs to the field of heterocyclic compounds, and in particular relates to a production process of a rubber vulcanization accelerator MBTS. The process includes the following steps: (1) Mix MBT and solvent under stirring conditions to obtain a raw material liquid; (2) Put the raw material liquid obtained in step (1) into an autoclave, and then add a catalyst with a tertiary amino group Porous anion exchange resin, after starting the stirring, air is introduced to a pressure of 0.7-4Mpa, and the oxidation reaction begins; during the process, the reaction temperature is controlled at 30-60°C, and the total mass of the air is 0.23-0.4 times the mass of the input MBT , stop feeding air, and continue to stir until the reaction is over; (3) After the pressure in the kettle is released, the material is first passed through a filter to recover the catalyst, and the filtrate is filtered through a medium-speed filter paper for a second time, and after washing with water, the target product can be obtained. Product MBTS.

Description

technical field [0001] The invention belongs to the field of heterocyclic compounds, and in particular relates to a production process of a rubber vulcanization accelerator MBTS. Background technique [0002] In the process of using rubber to produce various rubber products such as tires, hoses, and rubber shoes, five types of additives must be used, which are rubber vulcanization accelerators (referred to as accelerators), rubber antioxidants, rubber vulcanization and vulcanization active agents, Type rubber additives and special functional additives. The vulcanization accelerator is called accelerator for short. Substances that promote vulcanization. It can shorten the vulcanization time, lower the vulcanization temperature, reduce the amount of vulcanizing agent and improve the physical and mechanical properties of rubber. [0003] Rubber vulcanization accelerator MBTS (chemical name 2,2'-dithiodibenzothiazole, also known as DM) is a general-purpose accelerator for nat...

AI Technical Summary

Problems solved by technology

This process is mature, but about 10-15 tons of high-salt and high-organic waste water is produced per ton of product. Currently, it can be seen that the reported wastewater treatment processes are all costly, and at the same time, waste salt NaCl of average quality is produced, which is difficult to treat.

[0006] 2) At 55-65°C, use a mixture of hydrogen peroxide and sulfuric acid as an oxidizing agent to directly oxidize 2-mercaptobenzothiazole sodium salt. When the pH is stable at 6.5-7.5, the reaction ends, and the solid-liquid separation is carried out at a controlled temperature of about 30°C. , the product DM is obtained, about 8-10 tons of saline organic wastewater is produced per ton of product, the treatment cost is high and Na2SO4 will be produced, which is difficult to handle

[0007] 3) MBT is oxidized with hydrogen peroxide, and MBTS is prepared with isopropanol as a carrier. Isopropanol can be recycled. Although this process uses an environmentally friendly oxidant, it reduces the pressure on environmental pollution, but the concentration of hydrogen peroxide is 27.5%. A large amount of organic waste water is produced, which increases the separation process of mother liquor. The distillation of mother liquor requires a lot of energy, which increases the production cost, and the process is complicated and difficult to operate.

[0008] 4) After dissolving MBT with ammonia water or liquid ammonia, the obtained ammonium salt solution is filtered, and the catalyst is added to react with oxygen or air for a certain period of time at a certain temperature and pressure to obtain the MBTS product. This process is complicated to operate, and the ammonium salt solution needs to be filtered. , the whole process needs a catalyst, and the content of ammonia nitrogen in the wastewater is high

Although this scheme uses oxygen as the oxidant, since the process yield is generally less than 90%, the by-products are mostly dissolved in ammonia water, so that the process still produces a large amount of wastewater that is difficult to treat, and the ammonia nitrogen content in the wastewater is often extremely high

Although the patent proposes that no three wastes are produced, the catalyst NO / NO2 itself is a gas pollutant, and the process makes the catalyst unable to realize recycling

In addition, the MBTS product yield of this technology is about 96%, that is, about 4% of the by-products will be dissolved in the solvent water or methanol, ethanol, isopropanol, benzene or toluene, and the by-products will reach saturation in the repeated application process At this time, the mother liquor cannot continue to be used mechanically, and then waste water or waste solvent will be produced, and this part of waste water or waste solvent and by-products belong to solid waste and waste liquid

[0010] To sum up, the currently commonly reported MBTS synthesis technology cannot effectively avoid the generation of the three wastes, and the generated "three wastes" also have the problems of difficulty in processing and high processing costs. It is necessary to develop a new MBTS synthesis process to solve or Alleviate the above problems

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