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-The aim of this work was the study on the separation of soybean oil/n-butane mixtures using a commercial hollow fiber ultrafiltration membrane (50 kDa). Oil/n-butane mixtures with mass ratios of 1:1 and 1:3 (wt), with the feed pressures of 5, 7 and 10 bar and transmembrane pressure of 1 bar were studied. Rejections of oil between 21 to 97.2%, oil fluxes between 0.04 and 0.98 kg/m 2 h and n-butane fluxes between 4 and 46 kg/m 2 h were observed, strongly influenced by the feed concentration. The increase in oil/n-butane mass ratio caused an increase in oil rejection and a decrease in the permeate flux of oil for most assays. The increase in the operating pressure caused an increase in oil flux and a consequent decrease in oil rejection. No degradation was observed in the membrane module during the operation with this non-aqueous feed stream, as confirmed by integrity tests.

This work reports experimental data on the desorption of pure propane and n-butane from refined soybean oil at low pressures. The desorption parameters investigated were the overall solvent (normally gaseous at ambient conditions) content and solution stirring rate. Solvent mass fraction ranged from 1 to 10 wt% and stirring was studied in the interval between 0 and 200 rpm (equivalent to a Reynolds number 2 Â 10 7 ). Results showed a fast solvent release from the binary propane-soybean oil system, while a relatively slower liberation was noticed for soybean oilÀn-butane, due possibly to the much smaller solubility exhibited by the former solvent. The experimental information reported in this work may be of great technological relevance, since no desorption data were found in the literature for the systems investigated in this work.

Separation of refined soybean oil/n-hexane miscellas was studied using different commercial ultra-and nanofiltration membranes, with cutoffs in the range of 1 to 5 kDa and salt rejection higher than 97% (MgSO 4). Commercial soybean oil and n-hexane miscellas with 1:3 and 1:1 mass ratios were permeated in a dead-end module. The effects of the feed pressure (2-25 bar) on oil and n-hexane fluxes and rejection were investigated. Oil rejection ranged from negative values to 30.8%, soybean oil flux from 28.9 to 617.8 g/m-2 h-1 and n-hexane flux from 8.5 to 1,078.5 g m-2 h-1. Membrane fouling was observed at all experimental conditions studied. The membrane separation process has proven to be a promising alternative to solvent recovery in soybean oil extraction.