Patent ID: 8742182

Claim:
A process for the production of 1,2-dichloroethane, the process comprising: a direct chlorination step, wherein ethylene and chlorine are combined to form 1,2-dichloroethane and heat is generated by the process; an oxychlorination step wherein additional 1,2-dichloroethane is produced from ethylene, hydrogen chloride and oxygen; a fractioning purification step wherein the 1,2-dichloroethane is freed from byproducts; and a pyrolysis step wherein 1,2-dichloroethane is thermally cracked, the cracked gas comprising monomer vinyl chloride, hydrogen chloride, unreacted 1,2-dichloroethane and byproducts, wherein the unreacted 1,2-dichloroethane is returned to the fractioning purification step; wherein the heat from the direct chlorination step is used for the removal of water and lower-boiling components than 1,2-dichloroethane, wherein at least part of the heat from condensation of the water vapor from the distillation column is used to concentrate caustic soda by evaporation.