Abstract: A process for recovering N-methyl-2-pyrrolidone from an effluent stream in a poly(arylene sulfide) process containing N-methyl-2-pyrrolidone contaminated with acidic compounds and high boiling contaminants by contacting the kettle liquid from a heavies fractionation zone with an inorganic compound selected from the group consisting of alkaline earth oxides and alkaline earth hydroxides in an amount effective to reduce the acidic compound content of the kettle liquid, and introducing the treated kettle liquid into a thin film evaporation zone to produce an overhead product containing N-methyl-2-pyrrolidone and a bottoms stream containing N-methyl-2-pyrrolidone soluble reaction products of the acidic compounds with the inorganic compound, unreacted acidic compounds and high boiling contaminants.

Abstract: A method for recovering granular poly(arylene sulfide) from a polymerization reaction mixture at a temperature above that at which poly(arylene sulfide) is in molten phase comprising polar organic solvent and poly(arylene sulfide) in which, in the presence of a sufficient amount of separation agent to cause a phase separation of molten poly(arylene sulfide) and polar organic solvent, the temperature of the polymerization reaction mixture is reduced sufficiently to solidify the poly(arylene sulfide) to produce a slurry comprising particulate poly(arylene sulfide) in polar organic solvent. In a preferred embodiment a slurry comprising particulate poly(phenylene sulfide) in N-methyl-2-pyrrolidone is produced using water, and optionally an alkali metal carboxylate, as separation agent.

Abstract: Butadiene is produced in relatively pure form by an oxidative dehydrogenation process in which a crude butadiene stream comprising butadiene, butylenes, vinyl acetylene and propylene is first extractively distilled with an extractant consisting of a sulfolane/acetone mixture. From a purified stream consisting essentially of butadiene and vinyl acetylene, the vinyl acetylene in a second extractive distillation step is removed using a sulfolane/acetone mixture as the extractant to produce a pure butadiene stream.