Adsorption of Nickel(II) Ion From Aqueous Solution onto ZnCl2 Activated Carbon Prepared From Delonix Regia Pods (Flame Tree)

Adsorption of Nickel(II) ion onto Activated Carbon prepared from Delonix regia pods activated with Zinc chloride (DRZAC) under various experimental conditions were studied. Batch mode adsorption experiments were conducted. The characteristics of the DRZAC were determined by SEM, XRD, FTIR, BET analysis and pHZPC. The maximum removal efficiency of Ni(II) ion is 85% at pH 6. Under the chosen conditions, Experimental data obtained were fitted with linearised forms of Legergren and Ho kinetic models. The Sum of Error Squares Percentage (SSE %) for first order and second order kinetics were 1.56 & 0.72 respectively. Thus this adsorption followed second order kinetics. The equilibrium adsorption data were analyzed with four isotherm models. Order of best fitting isotherm models were found to be Freundlich >Tempkin >Langmuir >Dubinin Raduskevich. The results in this study indicated that DRZAC could be employed as an adsorbent for the removal of Ni(II) ion from an aqueous solution.