Chinese J. Chem. Eng., 14(1) 37—45 (2006) Fouling-resistant Composite Membranes for Separation of Oil-in-water Microemulsions*

Abstract Fouling-resistant ceramic-supported polymer composite membranes were developed for removal of oil-in-water (O/W) microemulsions. The composite membranes were featured with an asymmetric three-layer structure, i.e., a porous ceramic membrane substrate, a polyvinylidene fluoride (PVDF) ultrafiltration sub-layer, and a polyam-ide/polyvinyl alcohol (PVA) composite thin top-layer. The PVDF polymer was cast onto the tubular porous ceramic membranes with an immersion precipitation method, and the polyamide/PVA composite thin top-layer was fabricated with an interfacial polymerization method. The effects of the sub-layer composition and the recipe in the interfacial po-lymerization for fabricating the top-layer on the structure and performance of composite membranes were systematically investigated. The prepared composite membranes showed a good performance for treating the O/W microemulsions with a mean diameter of about 2.4µm. At the operating pressure of 0.4MPa, the hydraulic permeability remained steadily about 190L·m－2·h－1, the oil concentration in the permeate was less than 1.6mg·L－1, and the oil rejection coefficient was always higher than 98.5 % throughout the operation from the beginning