Investigation of the Ni(II) Adsorption, in Respect to Kinetics and Thermodynamics, by Carbonized Walnut Shell from Aqueous Solution

Bircan Kose, Saliha Erenturk

The objective in this study was to investigate the adsorption, in terms of reaction speed and thermodynamics, of the Ni(II) from aqueus solution. Carbonized walnut shell was used as an adsorbent. The effect of contact time (0-90min) and temperatures (26-45°C) on the adsorption properties have been studied. The adsorption process follows the pseudo-second-order kinetic model very well. The thermodynamic parameters, such as Gibb's free energy change (ΔG°), standard enthalpy change (ΔH°) and standard entropy change (ΔS°) were also evaluated. The thermodynamic parameters (ΔG° < 0, ΔS = -17.37 J/mol/K, ΔH° = -5.72 kJ/mol) indicated that it was a spontaneously exothermic reaction.