PROCESS FOR PURIFICATION OF CRUDE GLYCERIDE OIL COMPOSITIONS

摘要

A glyceride oil (e.g. soybean oil) containing gum material including phospholipid, e.g. lecithin, as a main impurity is purified by dilution with an organic solvent (e.g.) hexane), introducing the solution (e.g. from tank 11) under pressure into a spiral type or pleat type semipermeable membrane module (12) to separate it into membrane-permeable (13) and membrane-impermeable (15) liquids, introducing the resulting concentrated membrane-impermeable liquid (15) under pressure into an internal pressure type tubular semipermeable membrane (16) having an inner diameter of 2 to 25 mm to separate it into a membrane-permeable and a membrane-impermeable liquid, and removing the organic solvent from at least one of these liquids to obtain a purified glyceride oil and/or a purified phospholipid. Details are given of the construction of a spiral type membrane module having a central support; and of preferred polyimides for the membranes, which allow passage of molecules of mol wt. 10,000 to 100,000.