Separation of refined soybean oil/n-butane mixtures was studied in this work using different commercial ultra- and nanofiltration membranes, with cut-offs ranging from I to 5 kDa. Refined soybean oil/n-butane mixtures at 1:3 (w/w) and 1: 1 (w/w) mass ratios were continuously fed to a tangential flow module. The effects of the feed pressure (10-25 bar) and the transmembrane pressure difference (1-10 bar) on oil flux and retention were investigated. Oil retention results ranged from 52.8 to 99.1% and n-butane flux up to 2730 g/m(2) h were obtained. Membrane fouling was observed in all experimental conditions studied. The membrane separation process has proven to be a promising alternative to the recovery of the pressurized solvent. (C) 2009 Elsevier B.V. All rights reserved.