Synthesis of fatty alcohol mixtures from oleochemicals in supercritical fluids

Hydrogenation of various types of oleochemicals is a major unit operation in industry. Traditional methods utilize batch, stirred reactor operation resulting in long reaction times and excessive use of catalyst and hydrogen. In this study, reduction of fatty acid methyl esters (FAME) to fatty alcohol mixtures in two different types of supercritical media (H2/CO2 and H2/C3H8) were compared using two different hydrogenation catalysts. High and rapid conversions are achieved at the highest experimental temperature (250 °C) and at a hydrogenation mole fraction of 0.25. The described hydrogenation methods has been coupled with an enzymatic-catalyzed transesterification to yield a novel sequential two step synthetic procedure, which permits high fatty alcohol yields to be achieved directly from soybean oil.