Optimization of the Selective Adsorption of Cu2+ Versus Ni2+ and Zn2+ in the Multi-Ion System With Activated Carbons Prepared by Ultrasound

Abstract

In this study, optimization of the selective Cu 2+ adsorption from multi-ion media containing Cu 2+ , Zn 2+ and Ni 2+ on activated carbons (AC) prepared from ultrasound-assisted 10 % KOH impregnated hazelnut shells was investigated. For the suitable activated carbons production of selective adsorption of Cu 2+ from multi-ion media, the effects of independent variables such as particle size, ultrasound power density, impregnation rate, impregnation time, activation temperature and activation time were investigated by experiments with partial factorial and central composite design. At the end of the adsorption experiments, activated carbons were evaluated by their adsorption capacities. Additionally, the results were statistically modelled and optimized by using a constrained optimization program via Matlab computer software. The results of the experiments revealed that activated carbon prepared by ultrasound method can be used for the selective Cu 2+ adsorption from multi-ion system efficiently. The selectivity sequence based on the distribution coefficient (Kd) is generally Cu +2 > Zn +2 > Ni +2 for the multi-ion system. Finally, maximum adsorption capacity was found as 82.9 mg Cu 2+ /g Ac under optimum conditions such as particle size 1.7504 mm, ultrasound power/volume 2 W/L, impregnation ratio 0.0168 g/mL, impregnation time 132 min, activation temperature 661 •C and activation time 71.5 min.