Patent ID: 6979754

Claim:
A method for obtaining vinyl chloride capable of polymerization and formed from all of a cooled raw product derived from pyrolysis of 1,2-dichloroethane and having undergone a cooling operation, comprising: (1) providing said cooled raw product, wherein said cooled raw product comprises a mixture of a gas phase and a liquid phase, the gas phase and the liquid phase being in equilibrium with each other, the mixture comprising vinyl chloride, hydrogen chloride, unconverted 1,2-dichloroethane and 1,3-butadiene; (2) conveying all of said cooled raw product to a falling-film type heat exchanger and subjecting said cooled raw product to a further cooling operation under a pressure greater than atmospheric pressure to at most 15 bar and a temperature of at most 40° C.; (3) conveying all of said further cooled raw product from the falling-film type heat exchanger to a receiving pot, wherein the pot has a temperature and a pressure that are substantially identical to the temperature and the pressure, respectively, in the falling-film type heat exchanger, wherein the liquid phase of the further cooled raw product is permitted to remain in the pot for a period of at most 20 minutes; (4) conveying the further cooled raw product to a first distillation column and subjecting the further cooled raw product to a first distillation process to separate hydrogen chloride from the further cooled raw product, thereby forming a first distillation product comprising vinyl chloride and unconverted 1,2-dichloroethane; (5) conveying the first distillation product to a second distillation column and subjecting the first distillation product to a second distillation process to separate vinyl chloride from the first distillation product; and (6) conveying the separated vinyl chloride to a purification apparatus and subjecting the separated vinyl chloride to a purification process to remove residual hydrogen chloride therefrom, thereby forming a purified vinyl chloride capable of polymerization.