Removal of oleic acid from sunflower oil on zeolite 13X: Kinetics, equilibrium and thermodynamic studies

The experimental parameters for adsorption of oleic acid from oleic acid-sunflower oil mixtures has been investigated by using zeolite 13X. The effect of adsorption parameters such as contact time, temperature and adsorbent amount was studied. The experimental results were analyzed by using pseudo first order and pseudo second order kinetic models and Langmuir, Freundlich and D-R isotherms. The results fitted the pseudo second order kinetic model at 50 degrees C and 75 degrees C. It was also observed that adsorption process followed both pseudo first and second order kinetic models at 30 degrees C. The Freundlich isotherm model provided the best fit for all studied temperatures. The thermodynamic parameters of adsorption system; Delta G(0), Delta H-0 and Delta S-0 were determined. Thermodynamic study showed that oleic acid adsorption onto the zeolite 13X was spontaneous and endothermic process. After the desorption study, 91.60% of oleic acid was desorbed from the zeolite 13X. (C) 2015 Elsevier B.V. All rights reserved.