Effect of Possible Interferences on the Extraction of 1-Butanol from Aqueous Solution by the Ethyl Esters of Soybean Oil Fatty Acids

The methyl, ethyl, propyl and butyl esters of vegetable and tree oils are effective solvent extractants for 1-butanol from aqueous solution. Early applications of this process will probably involve bacterial mixed solvent fermentations of relatively impure waste and low-valued carbohydrates. Two types of materials, salts and solvents, could be expected to affect the extraction of 1-butanol from such industrial fermentation systems. The effect of four salts, three alcohols, and a ketone were evaluated using factorial experiments. Variations in NaCl, Na 2 SO 4 , Na 2 SO 3 , and KHPO 4 from 0 to 0.15 M on the extraction of 0.1 to 4.1% 1-butanol from aqueous solutions at 25,40, and 55 C gave small changes in distribution coefficient. Mild increases occurred with increasing teperature and increasing NaCl, Na 2 SO 4 , and KH 2 PO 4 . Mild decreases in 1-butanol extraction occurred with increasing Na 2 SO 3 . Variations in acetone, ethanol, and 2-propanol concentrations ranging between 0 and 4% w/v at 25, 40 and 55 C gave small changes in distribution coefficient at 1-butanol concentrations ranging between 0.1 and 4.1% w/v had little effect. A slight increase in 1-butanol extraction was observed with increasing 1-pentanol under similar conditions.