Simulation of the supercritical CO2 extraction from natural matrices in packed bed columns: User-friendly simulator tool using Excel

Abstract

The aim of this work was to develop a user-friendly Excel interface to adjust the yields of an extraction column for SCF extraction. Moreover, this program could simulate the dynamic concentration profiles inside the column, being a useful teaching tool. The model comprises non-stationary mass balances for recovered compounds in both phases (solid and supercritical CO2). The model was tested by reproducing the extraction of two samples: sesame seeds and coffee beans (average deviations of 7.41% and 10.35%, respectively). These samples were selected to demonstrate the feasibility of reproducing processes whose mass transfer limitation is different. Thus, for the sesame seeds, the extraction process was controlled by both the external mass transfer and oil solubility, since the seeds were grinded. On the contrary, for coffee grains, the internal diffusion controls the extraction as the whole grain is required. Regarding solubility, a Henry’s relation between solid and CO2 concentration was assumed.