A green electrorefining process for production of pure lead from methanesulfonic acid medium

A green electrorefining process for production of pure lead from methanesulfonic acid (MSA) medium was studied. The conductivities of lead - MSA solutions have been measured and modeled to characterize the electrorefining medium. The effects of current density, electrode spacing, electrorefining temperature, lead concentration, free-MSA concentration and electrorefining time on the electrorefining process were investigated. The cell voltage and specific energy consumption of the electrorefining process increase with an increase of current density, electrode spacing and electrorefining time, and decrease with an increase of electrorefining temperature, lead concentration and free-MSA concentration. The operating parameters of the electrorefining process for production of pure lead from MSA medium in this study have a widely acceptable range as follows: current density 150-250 A/m2, electrode spacing 3.0-6.0 cm, electrorefining temperature 293.5-313.5 K, lead concentration 60-150 g/L and a free-MSA concentration 100 g/L. The cathodic current efficiency was in excess of 99% and the specific energy consumption was below 110 kW h/t-Pb. The lead content of the cathodic lead was in excess of 99.99%.