Solvent recycling method and butyl rubber production method

Abstract

The invention relates to the field of butyl rubber production, and discloses a solvent recycling method and a butyl rubber production method. The obtained halogenated rubber solution I is introduced into the coagulation tank to obtain a colloidal particle water slurry and a gas phase stream I; the gas phase stream I is subjected to condensation and water removal treatment to obtain a liquid phase alkane stream I; and drying to obtain a gas-phase alkane stream II; the gas-phase alkane stream II is recycled to participate in the refining I process of the crude gum liquid, and the gas-phase paraffin stream III obtained from the refining I process is recycled as a At least partially replace the solvent. The invention provides a more economical and practical process method for recycling the alkane solvent, which greatly saves the energy consumption in the production process of butyl rubber.

Description

technical field [0001] The invention relates to the field of butyl rubber production, in particular to a solvent recycling method and a butyl rubber production method. Background technique [0002] Halogenated butyl rubber, including brominated and chlorinated isobutylene-isoprene rubber, brominated isobutylene-p-methylstyrene rubber, etc., its production process mainly includes four parts: (1) production of base rubber; (2) Preparation of glue solution; (3) Halogenation reaction of glue solution; (4) Coagulation and drying of product. [0003] Since the production of butyl rubber generally adopts the low-temperature slurry polymerization process with chloromethane as the diluent, and the halogenation reaction generally adopts the solution halogenation process with alkane (such as hexane or cyclohexane) as the solvent, the glue preparation process It is actually a solvent replacement. [0004] For the preparation process of the glue solution, the low-temperature slurry hot...

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Problems solved by technology

[0005] This sol process not only has many procedures, but also has a long route. The most important problem is that monochloromethane is seriously hydrolyzed when it encounters hot alkaline water, and the monochloromethane with a higher amount of water must be dried in a drying tower and remove hydrolyzed impurities such as methanol and dimethyl Ether can be recycled, not only the regeneration of the drying tower is frequent, but also the monochloromethane exhaust gas discharged from the drying tower needs to be incinerated and harmless before being discharged.

Therefore, if the water coagulation and then dehydration sol process is adopted, the loss of monochloromethane usually reaches 30kg / t dry glue, and the burden of environmental protection treatment is relatively heavy.

[0006] In the prior art, in the process of granulating the sol, the surface of the rubber block cut by the cutter becomes sticky in the hexane vapor environment, and it is thrown on the wall of the sol pipe to be bonded. After more than 20 hours of equipment operation, the pipe will be completely Blockage requires regular pipeline cleaning. The cleaning time is about ten hours, and the sol cannot be continuously stabilized.

If two sol equipments are cleaned at the same time, the sol process is completely interrupted, resulting in unstable glue concentration (the difference in glue concentration is as high as ±5), and further, when the glue is undergoing halogenation reaction, the utilization rate of halogen is unstable, and the Unstable halogen content

[0007] In addition, in existing industrial production, strong alkali sodium hydroxide aqueous solution is used to forcibly neutralize the catalyst, which will lead to unstable polymerization reaction, especially reflected in the asymptomatic drift of product Mooney viscosity (Mooney viscosity drift) in the process of producing butyl rubber Up to ±10), difficult to adjust and control, resulting in uncontrollable by-products, affecting economic benefits

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