(1,2)-Dichloroethane prodn. from ethylene and chlorine - continuously in liq. phase with control of catalyst concn. in circulating liq.

摘要

Continuous prodn. is by liq. phase reaction of ethylene and Cl2 in an organic solvent contg. a chlorination catalyst dissolved therein. The reaction mixt. is circulated continuously through a reaction zone heated to 20-60 degrees C and a heat-exchanger to remove heat of reaction, fresh ethylene and Cl2 being added continuously to the circulating liquid and 1,2-Dichloroethane being withdrawn. A given amt. of catalyst is maintained in the circulating liquid, by returning a portion of the circulating liquid through a zone contg. the chlorination catalyst and into the reaction zone and by continually passing the circulating liquid into an analyser in order to establish the catalyst concn. The value found is then electronically controlled in the portion of the circulating liquid flowing through the catalyst zone by means of an impulse transformer such that too high a catalyst concn. in the circulating liquid is suppressed and reversed.