A continuous process for the production of epichlorohydrin

Claim 1

A continuous process for the production of epichlorohydrin which comprises a) reacting allyl chloride, chlorine and water in a first reaction zone to produce an aqueous solution of dichlorohydrin, b) reacting said dichlorohydrin solution with an excess of a basic substance in a second reaction zone under conditions of temperature and contact time of the reactants whereby the dichloro­hydrin is substantially converted to epichlorohydrin, c) separating the formed epichlorohydrin rapidly and substantially completely from the aqueous reaction mixture as overhead by flash distillation, d) cooling said reaction mixture depleted in epichlorohydrin to a temperature below 70 °C, e) electrodialyzing said cooled reaction mixture in an electro­dialysis zone to afford: 1) an electrodialysis concentrate stream having an inorganic chloride content higher than said cooled reaction mixture feed to the electrodialysis zone, and 2) a diluate stream containing organic chloride compounds and having a lower inorganic chloride content than said reaction mixture feed, f) removing said concentrate stream of step (e), g) subjecting said diluate stream to reverse osmosis to form a retentate stream having a higher content of organic and inorganic chlorides than said diluate stream, and a permeate stream substantially depleted in both organic and inorganic chlorides, h) removing said retentate stream, and i) recycling at least part of said permeate stream to said first reaction zone.