Simeonov E.Yaneva Z.Chilev C.2024-07-102024-07-102024-07-102024-07-102018-02-232191-95502191-954210.1515/gps-2016-0179SCOPUS_ID:85041652328https://rlib.uctm.edu/handle/123456789/456A 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, Deff, was also presented. The model adequacy is verified with the experimental data and shows very good coincidence.enArticle