Clarification of Date Syrup by Activated Carbon: Investigation on Kinetics, Equilibrium Isotherm, and Thermodynamics of Interactions

Abstract

Abstract The present work studies the removal of colored components from date syrup by activated carbon powder. The clarification process was carried out at an experimental batch set up and the role of activated carbon content, temperature and residence time was investigated on adsorption efficiency. The experimental data were analyzed by intra-particle diffusion, pseudo first- and second-order models. The adsorption capacity of activated carbon increases with increase of process temperature. Adsorption kinetics could be best modeled by the pseudo second-order model. Also, Langmuir isotherm describes the equilibrium data variation better than Freundlich and Temkin equations. The feasibility of adsorption was evaluated by measuring color removal at three temperatures and Van’t Hoff equation was used for computation of Gibbs energy. Thermodynamically, the process is endothermic accompanied with increase in randomness and decrease in Gibbs energy. Finally, the optimum temperature for clarification of date syrup was determined to be 50°C.