sorption of cu(ii), zn(ii) and ni(ii) from aqueous solution using activated carbon prepared from olive stone waste

The performance of olive stone activated carbon (osac) for the sorption of cu^2+, zn^2+ and ni^2+ ions was investigated via batch technique. osac materials were prepared under different physical activation conditions. olive stone waste was activated with n2 and steam at 900°c at a 3.5h hold time (osac-3). the characterization for osac-3 was performed under bet-surface area, sem, density and ftir-spectrum. the optimum adsorption conditions were specified as a function of agitation time, initial metal concentration, ph, and temperature. the kinetic results were found to be fast and described well by the pseudo-second order model. the adsorption capacities were 25.38mg/g (cu^2+), 16.95mg/g (zn^2+) and 14.65mg/g (ni2+) which followed the sequence cu^2+ > zn^2+ > ni^2+. the spontaneous adsorption for all the studied cations, endothermic nature for both zn^2+ and ni^2+ ions and exothermic nature for cu^2+ ions were obtained. the results showed that osac-3 is an economically feasible material for cu^2+, zn^2+ and ni^2+ remediation from weak acidic contaminated effluents.