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An original transesterification route for fatty acid ester production from vegetable oils in a solvent‐free system

1997; Wiley; Volume: 74; Issue: 9 Linguagem: Inglês

10.1007/s11746-997-0037-9

1558-9331

N. Goma‐Doncescu, Marie Dominique Legoy,

Process Optimization and Integration

Abstract Wax ester production from a long‐chain alcohol and methyl ester has been investigated with an immobilized thermostable lipase (lipozyme IM from Novo Nordisk). The transesterification reaction rate was monitored in solvent‐free medium that was exclusively composed of the reactants and the enzyme. The transesterification is performed by simply mixing the two substrates in various stoichiometric amounts at a temperature range from 55 to 65°C under constant stirring in the presence of low concentrations of enzyme preparation (0.12 to 2%, w/w). Long‐chain reactants produce waxes of high molecular mass that induce low solubility and high viscosity. On average, high transesterification yields are obtained (around 95%). Thermodynamic parameters involving substrate concentration and temperature have also been investigated. The balance between optimal working temperature and the molar ratio of substrates in such a complex medium appears to be 60°C, with a molar ratio methyl oleate/stearyl alcohol of 1:0.5. Substrate inhibition due to stearyl alcohol has been observed. A study of kinetic parameters has confirmed these results.