1,2-Dichloroethane → 1,1,2-Trichloroethane

Participants

Reaction Conditions

Reaction Steps

3500 m3/ h of hydrogen chloride from pyrolysis of 1,2-dichloroethane, contaminated by 2500 ppm by volume of acetylene, 150 ppm by volume of ethylene 5 ppm by volume of vinyl chloride and 2 ppm by volume of ethyl chloride entered the process through line 1 under a pressure of 8 bar absolute. The hydrogen chloride was preheated in a steam-heated heat exchanger 2 to a temperature of 160° C. After the addition of 21.5 m3/ chlorine gas through line 3 under a pressure of 8.5 bar absolute, the mixture passed through line 4 to reactor 5 which was filled with 0.8 m3 of activated carbon coated with 16% by weight of CuCl2 and 16% by weight of MnCl2. The reactor was operated adiabatically. In reactor 5, the reaction between acetylene, ethylene and vinyl chloride with chlorine to give 1,1,2,2-tetrachloroethane, 1,2-dichloroethane and 1,1,2-trichloroethane occurred. The reaction mixtures left the reactor 5 through line 6. The reaction mixture contained an excess of free chlorine of 985 ppm by volume, measured at 7. The concentration of acetylene and ethylene were each below 1 ppm by volume. Six m3/ h of vinyl chloride gas under a pressure of 8 bar absolute were admixed with the HCl at 8, the reaction mixture flowed at a temperature of 125° C. under a pressure of 7.5 bar absolute via line 8a to reactor 9, which was filled with 0.5 m3 of the same carrier catalyst as in reactor 5 and was operated adiabatically,too. In reactor 9, the free chlorine in the hydrogen chloride stream after reactor 5 reacted with the vinyl chloride to produce 1,1,2-trichloroethane.

Provenance & Evidence