Kinetic model in dynamic extraction of momordica charantia

Abstract

Bitter gourd (Momordica charantia) which has been traditionally used in the treatment of type 2 diabetes mellitus (T2DM) was extracted using supercritical carbon dioxide (SC-CO2). The SC-CO2 is a fluid which possesses unique properties of high diffusivity and low viscosity. The aim of this study was to investigate the effect of different mean particle size in the determination of overall mass transfer coefficient using kinetic model of single sphere model (SSM) with the combination of simplified linear driving force model (LDFM). The mean particle sizes used were 0.20, 0.30, 0.50 and 0.70mm using 1:3 feed-to-solvent ratio of ethanol as co-extractant at constant operating conditions (4mL/min of SC-CO2, 65°C and 20MPa). The results showed that mean particle size of 0.30mm fit well in a kinetic model, SSM and simplified LDFM with the highest De value, i.e. 8.82 x 10-12m2/s. Furthermore, it shows a high mass transfer coefficient in fluid phase, kf and overall, kp value, i.e. 2.32 x 10-6 and 2.61 x 10-7m/s respectively. Based on the results, it can be concluded that 0.30mm is the best mean particle size to be used in the extraction of bitter gourd using SC-CO2 solvent.