1,2-Di:chloroethane prodn. - by reacting chlorine and ethylene@ in di:chloroethane as solvent, in presence of mixt. of ferric chloride and excess sodium chloride

摘要

Prodn. is of 1,2-dichloroethane (I) from chlorine and ethylene with (I) as solvent, at 30-100 deg.C in the presence of FeCl3 (II). (II) is used in combination with NaCl in the mol. ratio (1:1.5)-(1:2). USE/ADVANTAGE - Increases the selectivity of the large-scale process to such an extent that the prod. (I) is pure enough to be used directly for thermal cleavage to vinyl chloride, without prior distn. of high-boiling cpds.; separate prepn. of NaFeCl4 is not required. In an example, 106-m3 reactor, filled to the 80% level with (I), at 50 deg.C and 0.8 bar, was charged with chlorine at 4000 Nm3/hr. and ethylene at 4100 Nm3/hr., while (I) was removed at 17760 kg/hr. Amt. of (II) used was 0.2 kg/ton (I) produced. Prod. was worked up by washing with water to remove catalyst followed by distn. to remove low-boiling prods. and water. When NaCl was added to (II) at the rate of 110 kg/2 days (mol. ratio (II):NaCl = 1:1.83), a pure prod.was obtd., contg. 99.97% (I) and 0.022% 1,1,2-trichloroethane (cf. 99.87% and 0.125% when no NaCl was added; 99.93% and 0.065% when mol. ratio (II):NaCl = 1: