The Adsorption of Copper (II) and Nickel (II) by Zeolite from Single and Binary Systems
In this study, it was examined how temperature, pH and concentration from parameters influencing the adsorption process affects the binary adsorption process. We found optimum pH values as 5 for adsorption of copper and nickel on zeolite. The effect of initial concentration and ambient temperature on the yield of adsorption was examined at this pH value. The equilibrium adsorption data of Cu(II) and Ni(II) onto Zeolite were analyzed by the Langmuir and Freundlich isotherms, and the experimental data for the adsorption of both the metal ions fitted well with all the isotherm models. In single and binary sorption experiments, observed considerable difference is the metal uptake rate on adsorbent. According to the single sorption studies, the reason for low rate of metal uptake in the binary adsorption studies is the existence of competing metal ions. Thermodynamic parameters such as Gibbs free energy change and enthalpy change were calculated, and the equilibrium data showed that the intake of Cu(II) into Zeolite was possible, spontaneous and endothermic in nature. The calculated activation energy of adsorption and Gibbs free energy change showed that the adsorption of Cu(II) and Ni(II) onto Zeolite involves not only a chemical adsorption process, but also a physical adsorption process.