The employment of ethanol as solvent to extract Brazil nut oil

Abstract

Abstract The use of ethanol for oil extraction, focusing on the recovery of the residual oil from marc, is an alternative to increase the yield and also optimize the use of non-timber forest products of Brazilian biodiversity. For this reason, the liquid-liquid equilibrium data for pseudoternary systems containing Brazil nut oil + anhydrous ethanol + water and solid-liquid equilibrium data for semi-defatted Brazil nut marc + anhydrous ethanol were determined experimentally from 323.15 to 343.15 K. The adjusted NRTL parameters described the liquid-liquid equilibrium with average deviation between experimental and calculated compositions equal to 0.8271 % and the critical solution temperatures with correlation coefficient of 0.9986. Yield and solubility diagrams were obtained with the solid-liquid equilibrium data. When comparing in the same temperature and water content, the alcoholic phase (AP) from liquid-liquid equilibrium with the liquid phase (LP) from solid-liquid equilibrium, it was observed that the oil content in the alcoholic phase (AP) was always higher than that in the liquid phase (LP). This fact reinforces that the miscella oil concentration is influenced by the oil retention in the solid phase (SP). These data indicated the best conditions to use the ethanol to extract Brazil nut oil.