Low-mercury catalyst for hydrochlorination of acetylene

Abstract

The invention discloses a low-mercury catalyst and particularly relates to the low-mercury catalyst which is suitable for synthesizing vinyl chloride by hydrochlorination reaction of acetylene. The catalyst comprises a main active component, namely mercury chloride, auxiliary active components, namely at least one of oxides of cobalt, manganese, silver and copper and a carrier, namely activated carbon, wherein the mercury chloride accounts for 2-4% of the weight of the carrier of the catalyst, and the auxiliary active components account for 5-30% of the weight of the carrier of the catalyst in total. According to the prepared low-mercury complex catalyst disclosed by the invention, the auxiliary components are added, so that the anti-poisoning performance of the low-mercury catalyst is enhanced, the reduction of the mercury chloride during the using process is reduced, the loss of mercury is retarded, the service life of the low-mercury catalyst is significantly prolonged, and the low-mercury catalyst is the novel low-mercury catalyst with good activity, strong stability and high selectivity. The low-mercury catalyst has the advantages of simple production process, short production period and low mercury consumption.

Description

technical field [0001] The invention relates to a catalyst, in particular to a low-mercury catalyst used for acetylene hydrochlorination to synthesize vinyl chloride. Background technique [0002] Polyvinyl chloride is one of the five major synthetic resins in the world, widely used in important areas of the national economy such as industry, agriculture, and building materials. Vinyl chloride monomer is an important raw material for organic chemical synthesis. Its main purpose is to produce polyvinyl chloride resin and other vinyl chloride copolymers. With the development of social economy, its demand is increasing day by day. The sources of vinyl chloride mainly include calcium carbide acetylene method, petroleum ethylene method and dichloroethane cracking method. my country's energy structure of "short of oil, poor in gas, and rich in coal" determines that the production of polyvinyl chloride by calcium carbide acetylene has become the mainstream. Although calcium carbi...

AI Technical Summary

Problems solved by technology

These several patents have adopted a relatively low content of mercuric chloride as the main active component of the catalyst, and other metal chlorides as the auxiliary active component, with activated carbon or molecular sieve as the carrier, but due to the fact that the raw material gas contains H 2 S.PH 3 impurity, causing poisoning and deactivation of the catalyst, and because acetylene has a high reducibility, it is easy to make the main active component in the catalysis Hg 2+ converted to Hg 0 , resulting in catalyst deactivation and loss of mercury flow

Thereby lead to the deactivation of catalyst, so although the catalytic activity of above-mentioned low-mercury catalyst can meet the production requirements, its stability and anti-poisoning performance are relatively poor, the life-span is shorter, fail to obtain industrial application in acetylene hydrochlorination