Process for removing halogenated hydrocarbons from solvent streams

Abstract

A process is provided for recovering halogenated hydrocarbons from solvent streams, particularly those including water and at least one alcohol, ketone or ester impurity. The process also provides for the recovery of the alcohol, ketone or ester, which can be reused or incinerated. The solvent stream is condensed and initially spearated into a halogenated hydrocarbon rich fraction and a water rich fraction containing the impurities. Impurities are removed from the halogenated hydrocarbon rich fraction in a first separation step, preferably liquid-liquid extraction with water. The impurities are extracted from the halogenated hydrocarbons into the water, which is passed to the water fraction of the initial separation step for further treatment. Halogenated hydrocarbons leaving the extraction column are passed to a distillation column where remaining water and impurities are removed. A continuous halogenated hydrocarbon vapor draw is preferably removed and condensed from the distillation column. The halogenated hydrocarbon product from the distillation column can, if necessary, be further dehydrated prior to storage or reuse. The water rich fraction is processed in one or more separation steps to remove remaining halogenated hydrocarbons and impurities. The halogenated hydrocarbons are removed in a first water rich fraction distillation step, and the impurities are removed from the water in a second water rich fraction distillation step.