Lipase-Catalyzed Clycerolysis of Soybean Oil in Supercritical Carbon Dioxide

ABSTRACT: The transesterification of soybean oil with glyc-erol, 1,2-propanediol, and methanol by an immobilized lipase in flowing supercritical carbon dioxide ior the synthesis of monoglycerides is described. A lipase from Candida antarctica was used to catalyze the reaction of soybean oil with glycerol, 1,2-propanediol, ethylene glycol, and methanol. Reactions were performed in supercritical carbon dioxide at a density of 0.72 g/L and at a flow rate of 6 pUmin (expanded gas). The sub-strates were added at flows ranging from 2.5 to 100 pL/min. Monoglycerides were obtained at up to 87 wt%, and fatty acid methyl esters at nearly 100 wt%. The reactivity of the alcohols paralleled the solubility of the substrate in liquid carbon diox-ide. Glycerol has the slowest reaction rate, only 2 % of that of methanol. jA0C.S 74, 103-l 06 (1997)