Isopropanol as a solvent for extraction of cottonseed oil

Summary Phase equilibrium data for the system; cottonseed oil‐isopropanol‐water were determined at 30°C. and compared with data for the system; cottonseed oilethanol‐water. The relative phase distribution of fatty acids and cottonseed oil in mixtures with isopropanol and water was studied under varying conditions of water and fatty acid concentrations. These tests showed the fatty acids to be highly concentrated in the alcohol‐water phase. Flaked cottonseed meats were extracted in continuous extraction apparatus with 91% isopropanol, 99% isopropanol, and mixtures of commercial hexane and isopropanol. Analytical data on the extractions show that 91% isopropanol is an efficient solvent for extracting active gossypol along with the oil. Rat and swine feeding tests of the isopropanol extracted meal showed it to be highly superior to hydraulic meal as a source of protein. A method was developed for treatment of the cottonseed‐isopropanol miscella by liquid‐liquid extraction to separate purified oil and fatty acid fractions from other materials in the extract.