Alloy powders are commonly used in the purification of zinc sulfate solutions for use in standard ectrowinning practice. The primary goal of this research was to study the use of zinc-lead alloys (similar reactions in the galvanic stripping ofimpurities from organic solutions. The effects of various parameters on the electrochemical behavior of commercially produced zinc-lead alloy powders were determined. A qualitative evaluation and summary of the influence of the more pertinent parameterson iron removal from di-(2-ethylhexyl) phosphoric acid (D2EHPA) by galvanic stripping is given. Water concentration, oxygen content and reaction temperature were the principal factors affecting the reaction rate and process efficiency. Activation energies were also calculated and indicated that the reaction changes from chemical to diffusion control with increasing temperature in the range of 35°to 45°C. The results showed that zinc-lead alloy gave faster reaction rates with less sensitivity to processvariables than SHG zinc as a reducing agent for galvanic stripping. The role of lead could be as cathodic sites for the reaction which enhances the zinc dissolution or anodic half reaction. The morphology of the zinc4ead alloy surfaces, before and afterthe reactions, supports this assumption.
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