| 摘要 |
A process for the preparation of 1,2-dichloroethane by reaction of ethylene with chlorine in a solvent in the presence of a catalyst mixture consisting of anhydrous iron(III) chloride and a nitrogen base or a salt of this base, at a temperature below the boiling point of the 1,2-dichloroethane and removal of the 1,2-dichloroethane from the chlorination mixture, which is characterised in that a) the chlorination mixture is fed to a distillation column, the 1,2-dichloroethane is distilled off from the mixture until the catalyst precipitates from the liquid bottom product, the precipitated catalyst is removed from the bottom product and the latter is used again for reaction of ethylene with chlorine or in that b) the chlorination mixture is passed over an adsorbent, the catalyst contained in the mixture is adsorbed on the adsorbent, 1,2-dichloroethane is removed from the resulting filtrate by distillation and the catalyst is recovered from the adsorbent or in that c) the process is carried out according to a), but the catalyst-containing bottom product is discarded in the case of low contents of catalyst. |
