Effect of Different Parameters on the Adsorption of Zn(II) onto Charcoal Ash

Abstract

The aim of this research work is to investigate sorption characteristic of charcoal ash for the removal of Zn(II) from aqueous solutions and wastewater. The sorption of Zn(II) by batch dynamic method is carried out. The optimum conditions of sorption were found to be: a sorbent dose of 10 g in 100 mL of aqueous solutions, contact time of 2 h, pH 5. In optimum condition, removal efficiency was 96.1 for the Zn(II). Three equations, i.e. Morris-Weber, Lagergren and pseudo second order have been tested to track the kinetics of removal process. The Langmuir, Freundlich and D-R are subjected to sorption data to estimate sorption capacity. It can be concluded that ash has potential to remove Zn(II) ions from aqueous solutions at different concentrations. Desorption efficiency had been tested by water saturated with CO₂ and by aqueous solution of acetic acid, the results was not considerable. It was found that increasing temperature has positive effect on the adsorption, the thermodynamic parameters ΔH, ΔS and ΔG are evaluated. Thermodynamic parameters showed that the adsorption of Zn(II) onto ash was feasible, spontaneous and endothermic under studied conditions.