Reaction kettle device capable of controlling synthesis temperature of accelerant 2-mercaptobenzothiazole (MBT)

Abstract

The invention provides a reaction kettle device capable of controlling the synthesis temperature of an accelerant 2-mercaptobenzothiazole (MBT). An original high-pressure synthesis kettle is improved; a coil pipe is additionally arranged into the high-pressure synthesis kettle; the height of the coil pipe is 1 / 2-2 / 3 of that of a kettle body; the diameter of the coil pipe is 0.7-0.9 time that of the kettle body; an inlet and an outlet of the coil pipe are connected with a heat conduction oil inlet / outlet pipeline by seal heads of the kettle body. After the high-pressure kettle is fed, heat conduction oil is fed into the coil pipe in the reaction kettle for heating the reaction material. The temperature of the inlet heat conduction oil is controlled to be within the range of 240-250 DEG C; the reaction temperature is controlled to be within the range of 250-260 DEG C, and the reaction time is controlled to be 120-180 minutes. In a reaction process, the heat conduction oil is directly fed into the reaction kettle, so that the heat transfer resistance is reduced, and the heat transfer efficiency is improved; furthermore, the coil pipe is additionally arranged into the reaction kettle, so that internal mass transfer is enhanced, the temperature in the reaction kettle is uniform, the phenomenon of overheating is avoided, and the reaction promoting generation of the MBT can be carried out.

Description

technical field [0001] The invention relates to an improvement of a rubber vulcanization accelerator 2-mercaptobenzothiazole (MBT) synthesis kettle, and belongs to the technical field of rubber vulcanization accelerator MBT production. Background technique [0002] Accelerator MBT is a general-purpose rubber vulcanization accelerator, and it is also the parent material of most sulfenamide accelerators. Synthesis of accelerators such as benzothiazole zinc salt, sulfenimide, sulfenamide, etc., are inseparable from the development of accelerator MBT. The quality and output of accelerator MBT are directly related to the development of the rubber industry. At present, the high-pressure aniline method is generally used in China for production, such as figure 1 Shown: Aniline, sulfur, and carbon disulfide are put into a high-pressure reactor in a certain proportion, and react for 2-4 hours at a temperature of 250-270°C and a pressure of 10Mpa to synthesize the accelerator MBT. Th...

AI Technical Summary

Problems solved by technology

Although the temperature of the jacketed heat transfer oil has decreased, the general temperature of the heat transfer oil is 280-300 ° C, and there is also the problem of excessive temperature.

The higher the temperature, the easier it is for side reactions to occur, thereby reducing the yield and purity of MBT

Both of these two methods have the problem of heat transfer lag, and the control of reaction temperature is based on experience, so overtemperature and overpressure often occur, which affects the reaction yield. At present, the average yield of MBT is only about 82%.

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