NICKEL BIVALENT METAL ION ADSORPTION FROM AQUEOUS SOLUTION BY PREPARED ACTIVATED CARBON FROM PERGULARIA DAEMIA

Abstract

The activated carbon produced from Pergularia daemia stem was chemically activated using sulfuric acid and utilized as an adsorbent for the removal of nickel (II) from aqueous solution in the concentration range 10-50 mg/L. Adsorption experiments were carried out in a batch process and various experimental parameters such as effect of contact time, carbon dosage and pH on percentage removal have been studied. Adsorption results obtained, shows that the Ni (II) uptake being attained at pH 6.7. The equilibrium adsorption data was better fitted to the Langmuir’s and Freundlich adsorption models. Kinetic modeling of the process of removal was carried out and the process of removal was found to follow a pseudo second order model, Elovich model and Intraparticle diffusion model the value of rate constant for adsorption process was calculated. The thermodynamic parameters such as change in free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were determined and the negative values of ΔG° indicated that the process of removal was spontaneous at all values of temperatures. It was concluded that activated carbon produced from Pergularia daemia stem has an efficient adsorption capacity for removal of nickel bivalent mental ion.