Clean production method of chlorinated polyethylene

Abstract

The invention discloses a clean production method of chlorinated polyethylene. The clean production method adopts a hydrochloric acid phase suspension process which comprises the following steps: preparation of a supernatant solution, a chlorination process, a deacidification process, a centrifugation and drying process. The deacidification process includes two stages of filtration and deacidification; a chlorinated polyethylene slurry material is subjected to a first stage of filtration, a concentrated hydrochloric acid contained in the slurry material is filtered out and put into a concentration acid storage tank, subsequently the slurry material is subjected to a second stage of filtration, the acid residue in the slurry material is washed by water and filtered out to form a diluted hydrochloric acid, and then the diluted hydrochloric acid is put into a diluted acid storage tank. The production method disclosed by the invention has the beneficial effects that by the two stages of filtration and deacidification, the concentrated hydrochloric acid in the slurry material is totally recycled and sold after the chlorination reaction, and the diluted hydrochloric acid generated by washing the slurry material after the reaction is totally recycled as well, thus zero emission of acidic water generated after the chlorination reaction and during filtration and washing is realized, the energy conservation and emission reduction effects are obvious, the production cost is further lowered, and the production process is efficient, clean and environment-friendly.

Description

technical field [0001] The invention relates to a clean production method of chlorinated polyethylene. Background technique [0002] Chlorinated polyethylene is a polymer material obtained by chlorination substitution reaction of high-density polyethylene. It is mainly used as a resin impact modifier and synthetic rubber. [0003] At present, the main method of producing chlorinated polyethylene at home and abroad is the suspension method. There are two production processes of aqueous phase suspension method and hydrochloric acid phase suspension method in the production of chlorinated polyethylene by suspension method. The disadvantage of the aqueous phase suspension method is that water is used as the chlorination medium. After the chlorination reaction, the by-product hydrogen chloride is absorbed to form dilute hydrochloric acid with a weight concentration of 5%-6%. Due to the low concentration of hydrochloric acid, it is difficult to recycle and the waste water discharg...

AI Technical Summary

Problems solved by technology

The disadvantage of the aqueous phase suspension method is that water is used as the chlorination medium. After the chlorination reaction, the by-product hydrogen chloride is absorbed to form dilute hydrochloric acid with a weight concentration of 5%-6%. Due to the low concentration of hydrochloric acid, it is difficult to recycle and the waste water discharge is large. Heavy environmental pollution; the production process of the hydrochloric acid phase suspension method uses hydrochloric acid with a weight concentration of about 20% to prepare a hydrochloric acid phase suspension. After the concentrated acid is removed, the slurry needs to be further washed, and some dilute acid with a lower concentration will still be produced during the further washing process.