Abstract: By static adsorption experiment, the adsorption state of caffeine on caffeine imprinted phenolic resin sorbent (CIPS) and non-imprinted phenolic resin sorbent (NIPS) were compared. The results show that the adsorption datas are consistent with Freundlich equation in a certain range of concentration, so the adsorptions of caffeine on CIPS and NIPS are preferential adsorption. The isosteric adsorption enthalpy is within -19 kJ/mol--31 kJ/mol, which suggests that the force of recognition point between the caffeine and phenolic hydroxyl group is a hydrogen bonding force and the adsorption is an exothermic process. The adsorption free energy change and adsorption entropy change are all negative, which indicates that the occurrence of adsorption is spontaneous
Template and target information: caffeine
Author keywords: adsorption, caffeine, Molecularly imprinted polymers, Phenolic resin, thermodynamics