Patent ID: 8461286

Claim:
A process for the production of liquid epoxy resins, the process consisting essentially of: contacting a polyhydric phenol and an epihalohydrin in the presence of an ionic catalyst comprising at least one of a quaternary ammonium halide, a quaternary phosphonium compound, a sulfonium compound, and a basic ionic exchange resin to form a halohydrin intermediate reaction product; concurrently: reacting a portion of the halohydrin intermediate reaction product with an alkali hydroxide to form a solid salt suspended in a liquid mixture comprising a dehydrohalogenated product and unreacted halohydrin intermediate, wherein the alkali hydroxide is used at less than a stoichiometric amount; and removing water and epihalohydrin as a vapor from the reacting mixture; separating the solid salt from the liquid mixture; reacting at least a portion of the unreacted halohydrin intermediate with an alkali hydroxide in the presence of water to form an organic mixture comprising an epoxy resin and unreacted epihalohydrin and an aqueous solution comprising a salt; separating the aqueous mixture from the organic mixture; and separating the unreacted epihalohydrin from the liquid epoxy resin.