**5. Conclusions**

An approach focused on the triglyceride mass transfer coefficients, based on their concentration in alcohol during the oil-alcohol mixing process, led to quantitative assessments, which are associated with those obtained for the glycerol mass transfer in biodiesel separation constituted the phenomenological base used in the predictions of behavior of the reactive processes of transesterification of vegetable oil.

A heterogeneous model was validated for the alkaline transesterification of soybean oil (methanol, ethanol, NaOH), including values of the physical parameters (distribution and mass transfer coefficients) determined experimentally, varying in the intervals [1.01–1.62] and [2.05–4.78] <sup>10</sup><sup>2</sup> , respectively, while the mass transfer coefficients were in the order of magnitude in the range 10<sup>2</sup> to 10<sup>4</sup> s 1 for triglycerides and [1.20–7.42] <sup>10</sup><sup>3</sup> <sup>s</sup> <sup>1</sup> for glycerol. The kinetic behavior of biodiesel production was simulated using the specific reaction rates for each biodiesel produced by methanolysis and ethanolysis in the range of 25° C to 60° C.
