Simultaneous adsorption of acid and flavonoids from hawthorn juice onto resins

摘要

To explore the mechanism of adsorbates onto selected resin and provide a theoretical basis for the reduction of acidity in hawthorn fruit juice. In this study, the adsorption processes of titratable acidity (TA) and total flavonoids (TF) from hawthorn fruit juice onto macro-porous adsorption resins were studied. The experimental data were fitted by two widely used isotherm models namely, Langmuir and Freundlich. Kinetics of the adsorption processes were fitted by Pseudo-first-order, Pseudo-second-order kinetics, Elovich kinetics and Web and Morris intra-particle diffusion model. The experiment data showed D315 resin exhibited the highest adsorption capacity, Q(e) = 176.28 mg/mL, and selectivity coefficient, alpha = 3.588. The results also showed that the adsorption of adsorbates on D315 resin correlated better with the Langmuir isotherm model. The adsorption processes of adsorbates were better fitted by pseudo-second-order kinetics. In addition, the adsorption process of TA and TF on D315 resin is chemical adsorption, spontaneous and endothermic. The results indicated that D315 resin had a good adsorption effect on TA in hawthorn fruit juice and provided the theoretical basis for further exploration.