Modeling the supercritical fluid extraction of black pepper (Piper nigrum L.) essential oil

The fixed bed extraction of black pepper essential oil using supercritical carbon dioxide was modeled by the extended Lack's plug flow model developed by Sovova (Sovova's model). The experimental data were obtained for extractions conducted at 30, 40 and 50 degreesC, and 150, 200, and 300 bar, for two different types of ground black pepper (batches I and 2). The model parameters were evaluated from the experimental data. The fluid-phase mass transfer coefficient was obtained from the constant extraction rate (CER) period using a logarithmical solute mass ratio difference. The Sovova's model was able to describe the experimental data quite well. The best value for the extraction parameter, which relates the resistances of solid-phase mass transfer to fluid-phase mass transfer, was 0.12 and 0.25 for batches 1 and 2, respectively. The experimental data were well represented by the model for the mass ratio of solute present in ruptured cell to the initial mass ratio of solute equal to 65% and 38% for batches I and 2, respectively. (C) 2002 Elsevier Science Ltd. All rights reserved.