LEAD DIOXIDE ANODE

This document examines the application of lead dioxide (PbO₂) insoluble anodes, particularly PbO₂-coated titanium (PbO₂/Ti), in hydrometallurgical processes such as electrowinning of non-ferrous metals. It first outlines the industrial background and manufacturing capabilities of Suzhou Fenggang Titanium Equipment Manufacturing Co., Ltd., a producer of rare metal chemical equipment and insoluble anodes. The technical focus centers on mixed metal oxide (MMO) titanium anodes (notably RuO₂-based coatings) and PbO₂/Ti anodes, summarizing their composition, operating windows, and electrochemical performance. Comparative discussion of α-PbO₂ and β-PbO₂ highlights the superior properties of β-PbO₂, including higher oxygen evolution overpotential, better conductivity and hardness, finer grain size, reduced porosity, enhanced corrosion resistance, and larger active surface area, making it a preferred anode material in electrolysis. Typical operating conditions are provided for electrowinning nickel, zinc, cobalt, and copper, including pH, ion concentrations, temperature, and current density. Documented advantages of PbO₂/Ti anodes over conventional lead-based alloy anodes include lower weight, longer service life (1–2 times), improved current distribution via mesh structures, reduced sludge formation and labor, elimination of contamination from alloying elements, higher purity cathode copper (up to 4N5), and broader electrolyte compatibility. The document thus positions PbO₂/Ti insoluble anodes as efficient, durable, and environmentally favorable materials for modern hydrometallurgical applications.