A biphasic model describing soybean oil epoxidation with H2O2 in a fed-batch reactor

In the present work, the kinetics, mass transfer and heat transfer of soybean oil epoxidation with H2O2 have been studied in a fed and pulse-fed-batch reactor. The reaction has been performed with peroxyformic acid (PEA), generated in situ, by reacting concentrated hydrogen peroxide (60 wt.%) with formic acid (FA), in the presence of sulphuric or phosphoric acid as catalysts. The kinetic study also considers two important aspects occurring simultaneously with the epoxidation reaction, namely: the degradation resulting from the opening of the oxirane rings, and the hydrogen peroxide decomposition. Epoxidation is a highly exothermic reaction and the evolution of the temperature in the reactor over a period of time is strongly dependent on the amounts and way in which a mixture of H2O2 and formic acid is added to the mixture of oil and catalyst. In this paper, a biphasic kinetic model has been developed considering all of the occurring reactions in each phase, the partition of reagents and products between the phases and the evolution of any involved chemical specie along the time. Different kinetic runs have been successfully simulated after the evaluation, by mathematical regression analysis or by independent means, of all the kinetic and thermodynamic parameters of the model. The heat transfer properties of the used reactor have been determined following different approaches. In addition, the evolution of the temperature of the reacting mixture during the time has also been simulated with the developed mathematical model. (C) 2011 Elsevier B.V. All rights reserved.