Pottery glaze—An excellent adsorbent for the removal of Cu(II) from aqueous solution

In the present study,pottery glaze was investigated as an excellent adsorbent for the removal of Cu(Ⅱ) ions from aqueous solution.Effect of concentration,contact time,pH,and effect of electrolyte concentration,adsorbent doses and temperature were studied by using batch process to optimize conditions for maximum adsorption. Equilibrium isotherm data were analyzed using Langmuir,Freundlich and Temkin isotherms at 30,40 and 50℃. Thermodynamic parameters such as standard enthalpy change(ΔH0),free energy change(ΔG 0)and entropy change (ΔS0)were also evaluated.These parameters indicated that adsorption process is endothermic and spontaneous in nature.The mean energy calculated from Dubinin-Radushkeuich(D-R)isotherms showed chemical nature of adsorption.The kinetic data were evaluated using the pseudo-first-order and pseudo-second order kinetic equations and it was found that data best fitted pseudo-second-order model over a wide range of initial Cu(Ⅱ)concentrations supporting that chemisorption process was involved.The adsorption and desorption studies carried out by batch process suggested 100% desorption of Cu(Ⅱ)ions with 0.1 N HCl solution.