Kinetics of green solid-liquid extraction of useful compounds from plant materials: kinetics coefficients and modeling

A mathematical model for modeling solid-liquid extraction from plants was developed. Two extraction systems, System I Nicotiana tabacum L.- water and System II Geranium sanguineum L.- water , were investigated. The effect of agitation rate on the mode of the extraction process was studied, as the limit values in the case of internal diffusion for System I and System II were determined. The kinetics of extraction for both systems at determined technological parameters (temperature and solid/liquid ratio) was experimentally investigated. The values of the partial mass transfer coefficient, k , were determined by the Regular regime method. A four-parameter empirical model for prediction of the effective diffusivity, D eff , was also presented. The model adequacy is verified with the experimental data and shows very good coincidence.