Simulation of the Essential oil extraction kinetics of Xylopia aethiopica fruits from Congo Brazzaville. Fick diffusion, Peleg sorption and MichaelisMenton enzymatic models

The hydrodistillation extraction kinetics of Xylopia aethiopica fruit essential oil were modeled according to the phenomenological approach applied to Fick diffusion model, Peleg sorption model and Michaelis-Menton enzymatic model. All these models fitted experimental data. The assumptions underpining each model highlight the understanding of the process. It emerges that the essential oil releases completely at the washing step (> 90 %) with a rate constant 105 higher than those of diffusion step. This latter is the limiting step of the process. The end of the process can be estimated at 18.4 min (10t1/2) or at 36.8 min (20 t1/2) with a maximum yield varying between 3.84 and 5.09 % for the 3 studied samples. Exploring the mechanism of extraction by different complementary models improves significantly the understanding of the process and reinforces the predictive goal of this study