Removal of Cu²⁺ from Aqueous Solution using Fly Ash

Abstract

This research aims at investigating the utilization of fly ash as a low-cost adsorbent to remove copper ions from aqueous solutions such as wastewater. Fly ash dosage as well as initial copper ion concentration，temperature and pH value were varied to find the optimum conditions for Cu 2+ adsorption by fly ash. The results from sorption process showed that the maximum adsorption rate was obtained at 50 mg/L when different dosage of fly ash was added into the solution, and it could be concluded that decreasing the initial concentration of copper ion is beneficial to the adsorption ability of fly ash. With the increase of pH value, the removal rate increased. When pH was 6, the removal rate reached the maximum of 99.60%. When initial copper content was 50 mg/L, pH value was 6, the adsorption capacity of fly ash sample reached 0.98 mg/mg. The main removal mechanisms were assumed to be the adsorption at the surface of the fly ash together with the precipitation from the solution.