RT info:eu-repo/semantics/article T1 Supercritical carbon dioxide as solvent in the lipase-catalyzed ethanolysis of fish oil: kinetic study A1 Melgosa Gómez, Rodrigo A1 Sanz Díez, Mª Teresa A1 García Solaesa, Ángela A1 Paz Barragán, Esther de A1 Beltrán Calvo, Sagrario A1 Lamas, Daniela L. K1 Omega 3 K1 Lipase K1 Ethanolysis K1 Supercritical carbon dioxide K1 Chemical engineering K1 Ingeniería química AB Supercritical carbon dioxide (SC-CO2) has been used as green solvent in the lipase-catalyzed ethanolysis of fish oil by Lipozyme RM IM at mild, non-oxidative conditions and with no solvent residues. The effect of experimental conditions, initial substrate ethanol/oil molar ratio (2–38), pressure (7.5–30 MPa), and temperature (323.15–353.15 K) on equilibrium conversion, reaction rate and oxidative status of the products has been studied. No ethanol inhibition has been observed at high concentrations of ethanol, when putting in contact first the fish oil with the enzyme avoiding direct contact between the biocatalyst and ethanol. Operating pressure affected positively the reaction performance in the range investigated. Visual observation of the phase behaviour of the initial reaction mixture showed an “expanded liquid phase” that helped enhancing reaction rate, and a gas phase. Raising temperature accelerated the reaction up to a limit (343.15 K), observing higher enzyme thermal stability than in other reaction media (313.15 K). However, lipid oxidation increases with temperature. Up to 86 ± 1% FAEE yield has been found at MR = 6:1, 30 MPa and 323.15 K. Kinetic data have been correlated by using a mathematical model based on the elementary reactions of the 3-step transesterification. Kinetic rate constants, apparent activation volumes and energies are reported for the first time for a lipase-catalyzed ethanolysis reaction in SC-CO2. PB Elsevier SN 2212-9820 YR 2017 FD 2017-01 LK http://hdl.handle.net/10259/4567 UL http://hdl.handle.net/10259/4567 LA eng NO Spanish Government (MINECO) and the EuropeanRegional Development Fund (ERDF) forfinancial support of theproject CTQ2012-39131-C02-01. Financial support from the Juntade Castilla y León and European Regional Development Fund(ERDF) through project BU055U16 DS Repositorio Institucional de la Universidad de Burgos RD 24-dic-2024