Process for separation of salt from heavy ends wastes of glycerine manufacture

摘要

A process is described for separating salt (sodium chloride) from the polyglyceride-containing organic phase of the heavy ends waste or glycerine foots still bottoms obtained in conventional manufacture of glycerine via hydrolysis of epichlorohydrin or glycerol dichlorohydrins. In this process, the heavy ends wastes made up primarily of salt and polyclycerides and containing less than about 6% by weight water are treated at elevated temperatures with sufficient amounts of n-butanol to bring about precipitation of the salt followed by separation of the n-butanol-containing liquid phase substantially free of salt from the precipitated salt, cooling of the separated liquid phase to a temperature at which the n-butanol phase separates from the substantially salt-free polyglyceride phase without further salt precipitation and recovery of the n-butanol from the phase-separated polyglyceride phase. After recovery from the phase separated, substantially salt free polyglyceride phase, the n-butanol is suitably recycled to the first step of the process for use in precipitating additional quantities of salt from the heavy ends wastes.