Method for continuous purification of rubber vulcanization accelerator m by applying solvent

Abstract

The invention discloses a method for continuously purifying a rubber vulcanization accelerator M by using a solvent, which comprises the following steps: adding a vulcanization accelerator M crude product into a toluene washing solution for perform purification, filtering, sending the filtrate into a toluene mother solution tank to cool and recover the accelerator M, distilling the residual mother solution to recover the toluene, washing the filter cake with the recovered toluene, and drying to obtain the rubber vulcanization accelerator M pure product, wherein the toluene washing solution cooled filtrate formed by washing the filter cake enters a washing solution collecting tank for extracting and purifying the vulcanization accelerator M crude product. The method is simple in process, and the toluene is recoverable, thereby reducing the total amount of the toluene mother solution, lowering the energy consumption and enhancing the yield. The method has the advantages of low cost and small environmental pollution, provides technical supports for continuous production of the accelerator M, has favorable economic and environmental benefits, and conforms to the requirements for national clean production.

Description

technical field [0001] The invention relates to a purification method of a rubber vulcanization accelerator 2-mercaptobenzothiazole (accelerator M or MBT), and belongs to the technical field of rubber vulcanization accelerator M preparation. [0002] technical background [0003] Rubber vulcanization accelerator M (chemical name 2-mercaptobenzothiazole) is an ultra-speed accelerator for natural rubber, which also has the effect of a plasticizer. Its vulcanization critical temperature is low, and it is easy to cause early vulcanization of the rubber. It can be used alone Or used in combination with other accelerators, suitable for tires, rubber shoes, and industrial rubber products. [0004] Nowadays, acid-base method and solvent method are commonly used in the production of accelerator M. The production of accelerator M by acid-base method will produce high-salt organic wastewater, which is difficult and costly to treat, and is gradually replaced by solvent method. Patent CN...

AI Technical Summary

Problems solved by technology

This patent uses toluene to purify the accelerator M. In addition to the good solubility of the by-products of M, toluene also has a certain solubility to M, and the solubility is 0.8g / 100mL~1.3g / 100mL. When the accelerator M is purified, a part of the accelerator M enters the toluene, resulting in the loss of the accelerator M

Nowadays, no one recovers this part of M dissolved in toluene, and there is no effective method to reduce the loss of M. If the loss of accelerator M in the process of toluene purification can be avoided, the yield of accelerator M will be greatly improved.