The use of ultrafiltration for treatment of spent solvent cleaning rinses from nickel-plating operations: membrane material selection study

Solvent-resistant hollow-fiber OF membranes were selected by measurement of fiber swelling and treatability studies on spent solvent cleaning rinse. The experimental results indicated that the membranes made of both cellulose acetate (CA) and polyacrylonitrile (PAN) materials could tolerate the solvent present and were suitable for treating the spent solvent rinses, whereas polyethersulfone and polysulfone membranes were not suitable. The CA membrane had the lowest fouling tendency when treating the spent solvent rinse. The results also showed that retentions of the emulsified solvent and oil-grease for the CA membrane were above 96% and 80%, respectively, and the PAN membrane had better retention than the CA membrane. It was hypothesized that there might be a critical micellar concentration for oil-grease for the PAN membrane.