Ultrafiltration of vegetable oils Degumming by polymeric membranes

In this work, four different membranes synthesized in our laboratories have been tested for their permeation flux, phospholipid retention and stability in hexane during membrane degumming of crude soybean oil. Membranes were made of three different polymeric materials, i.e. Polyvinylidenfluoride (PVDF), Polyethersulfone (PES)and olysulfone (PSf), and prepared by the phase inversion process. Raw membranes were characterized by the molecular weight cut-off (MWCO)and the water permeability, Lh,w. Ultrafiltration (UF)of an oil-hexane miscella was performed in a stirred dead-end UF cell, pressurized with N2. All membranes were soaked in solvent of ecreasing polarities to minimize the action of solvent on pore size. Each membrane was tested with pure solvent first and the membrane permeability to pure hexane, Lh,h, was determined. The degumming experiments were carried out with a 25