Hydrochlorination of acetylene

The hydrochlorination of olefins is a weaMy exothermic reaction with heats of reaction ranging from 4 to 21 kj/mol (1—5 kcal/mol). The hydrochlorination of acetylene is more exothermic, 184 kJ/mol (44 kcal/mol). 

Hutchings, G.J. (1985) Vapor phase hydrochlorination of acetylene Correlation of catalytic activity of supported metal chloride catalysts. Journal of Catalysis, 96, 292-295. 

K. Shinoda, Vapour-phase hydrochlorination of acetylene over metal chlorides supported on activated carbon, Chem. Lett. 3, 219-220 (1975). 

B. Nkosi, N. J. Coville, and G. J. Hutchings, Vapour-phase hydrochlorination of acetylene with group VIII and IB metal chloride catalysts, Appl. Catal. 43(1), 33-39 (1988). 

Vinyl Chloride. Vinyl chloride is an important monomer in the manufacture of polyvinyl chloride and vinyl polymers. Two basic transformations are in commercial use.188-190 The catalytic hydrochlorination of acetylene, once an important... 

The catalytic hydrochlorination of acetylene demands high-quality... 

Vinyl Chloride. Approximately 16.5 billion lb of VCM were produced in the United States in 1999, making it one of the largest-volume petrochemicals. It has been reported that more than 35 percent of the global production of chlorine goes to the manufacture of VCM. Although most of the VCM comes from EDC by the route described previously, it can be obtained from other sources, including its production in the catalytic hydrochlorination of acetylene and as a byproduct in the synthesis of other chlorinated hydrocarbons. 

In this reaction, vinyl chloride, which is formed by the hydrochlorination of acetylene with hydrogen chloride, was not observed from the reaction mixture. This result shows that vinyl chloride does not participate in the formation of dichlorovinylsilane.82... 

Vinyl chloride is produced in the following industrial reactions (1) the thermal cracking of 1,2-dichlor-oethane, which is produced by the chlorination and/ or oxychlorination of ethylene and (2) the hydrochlorination of acetylene. The vast majority of vinyl chloride is used for the production of polyvinyl chloride (PVC) and the manufacture of copolymers with monomers such as vinyl acetate or vinylidene chloride. A much smaller proportion of vinyl chloride is used in the production of chlorinated solvents - primarily trichloroethanes. 

Figure 9-3. Technological scheme of production of the vinyl chloride monomer (1) plasma-chemical pyrolysis (2) cleaning from higher unsaturated hydrocarbons (3) hydrochlorination of acetylene (4) chlorination of ethylene (5) thermal pyrolysis of dichloroethane.

Monomer. VCM is produced industrially by two main reactions (1) hydrochlorination of acetylene and (2) thermal cracking of 1,2-dichloroethane produced by direct chlorination or oxychlorination of ethylene in the balanced process. Presently, more than 90% of the VCM prodnced is based on this route. 

At one time, hydrochlorination of acetylene was the major source of vinyl chloride. As the cost of production of acetylene increased, however, manufacturers of vinyl chloride sought other routes to this material. The starting material chosen was ethylene, which can be converted to vinyl chloride in two steps treating ethylene with chlorine gives 1,2-dichloroethane, which, when heated in the presence of charcoal or other catalyst, loses a molecule of HCl to form vinyl chloride. 

Hutchings, G. (1985). Vapor Phase Hydrochlorination of Acetylene Correlation of Cataljftic Activity of Supported Metal Chloride Catalysts, J. Catal, 96, pp. 292-295. 

Before ethene from naphtha crackers was readily available, VCM was produced by hydrochlorination of acetylene... 

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