Cementation of copper from spent copper-pickle sulfate solution by zinc ash

The cementation of copper from sulfate medium using zinc ash was carried out by batch experiments. The effects of the different factors on the cementation process such as the pH of the solution, copper and zinc ash ratio, shaking time, copper concentration as well as temperature were separately studied. The results showed that about 99% of copper could be recovered from the sulfate solution of initial pH=2 with solid/liquid ratio=0.05 after 30min of continuous shaking. Kinetic investigations showed that the cementation reaction follows a first order reaction and the activation energy was calculated. A flow sheet was proposed and the investigated method was successfully applied for the recovery of copper from pickling solution resulting from a metal finishing plant which indicates the efficiency of zinc ash for the removal of copper from aqueous solutions. [Display omitted] ► This work indicates the efficiency of zinc ash for the removal of copper ions from pickling sulfate solution. ► The cementation process is a first order reaction. ► The energy of activation is found to be 25.06kJmol−1.