Lead electrodeposition from aliphatic polyamines solutions

Abstract

Hydrometallurgical and pyrometallurgical processing of ores and concentrates generates large amount of various solid residues. These may contain significant amount of heavy metals, particularly lead is of great importance. It is present in form of anglesite, cerrusite or lead oxides. Hydrometallurgical processing of leaching residues, dusts, and fly ashes is used to recover valuable metals from these streams. Acid leaching in sulfuric acid solutions or spent electrolyte results in producing high amount of lead sulfate that is still very attractive material to fulfill demand of lead acid battery market. Aliphatic linear polyamines are solvent extracting agents very selective towards lead sulfate. Here we report the comparative tests of four different linear aliphatic homologs, namely ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine as potential extracting agents of lead sulfate. The core research was devoted to the possibility of direct electrodeposition of lead from various polyamines solutions. Electrochemical tests performed at current density 200 A/m2, 60 °C, with an addition of selected inhibitor showed the possibility to produce metal layer with 97.2% purity for triethylenetetramine. Graphical abstract