Adsorption of ibuprofen sodium salt onto Amberlite resin IRN-78: Kinetics, isotherm and thermodynamic investigations

Amberlite resin IRN-78 was used for the adsorption of Ibuprofen sodium salt (IBP) from liquid phase. The effects of solvent, initial concentration, solution pH, temperature and contact time were investigated. Adsorption studies were carried out in water and in ethanol. It was found that the adsorption capacity was dependent on pH. The optimum pH range was between 6 and 10. The maximum adsorption capacities on the IRN-78 were 1.266 and 0.611 mmol/g for IBP in water and in ethanol, respectively. The equilibrium data of the adsorption of IBP onto IRN-78 fit well to the Langmuir model. The separation factor (R (L) ) values were in the range of 0-1, indicating that the adsorption was favorable. The values of thermodynamic parameters including Delta G(0), Delta H-0 and Delta S-0 demonstrated that the adsorption of IBP onto IRN-78 was spontaneous and endothermic within the temperature range of 288-308 K. The adsorption process was controlled by physical mechanism rather than chemical mechanism.