Evaluation of models for supercritical fluid extraction

Various models available in the literature for the modeling of supercritical extraction process are studied and validated using published experimental data. The first model considers internal mass transfer coefficient as the controlling parameter for the extraction process. On the other hand, the second model analyzes the dynamic behavior of the extraction process by considering intra-particle diffusion and external mass transfer. These models have also been studied to understand the effects of various model parameters like intra-particle diffusion, mass transfer coefficients & operating parameters on cumulative extraction yield. The model proposed by Reverchon (1996) [13] predicts a cumulative yield within an error limit of +9% in the MATLAB simulation and +4% to −5% in the FEMLAB simulation. Also, the model proposed by Goto et al. (1993) [8] fits the experimental data of Kim et al. (2007) [19], Skerget and Knez (2001) [20], and Tonthubthimthong et al. (2004) [21] within an error band of +10% to −2%.