Experimental and Modeling Investigation of Supercritical Carbon Dioxide Extraction of Aloe vera leaf skin

Supercritical fluid extraction is a powerful technique in separation of antioxidants from plants. In this study, supercritical CO2 extraction of β-carotene from leaf skin of Aloe vera (Aloe barbadensis miller) was investigated and modeling of this system was developed in order to predict the extraction yield as a function of effective operating variables. The results of β-carotene extraction via supercritical CO2 were compared with the conventional Soxhlet extraction from Aloe vera skin using petroleum ether as the solvent. The shrinking core model was applied in the simulation which is similar to irreversible desorption of a solute from a porous adsorbent. The results showed that this model agrees well with the experimental data. β-carotene extraction yield was determined as a function of temperature, pressure, CO2 flow rate and dynamic extraction time.