Comparison of Hydrogen Reduction of Different Lead-Bearing Materials for Lead Recovery

Understanding the fundamental knowledge of leadLead reduction from lead-bearing materials using hydrogenHydrogen is essential for developing a carbon neutral leadLead production process. RecyclingRecycling of leadLead from secondary resourcesSecondary resource using hydrogenHydrogen as a reducing agent is industrially important to promote circular economy, resource efficiency, and reduction of carbon footprint. The current study evaluates and compares the general reduction mechanismReduction mechanism of PbOPbO with a more complex lead-containing compound, PbO-SiO2 glass/slagSlag. Isothermal reductions were carried out on pelletized PbOPbO and PbO-SiO2 (70wt% PbOPbO and 30wt% SiO2) using hydrogenHydrogen at 350 to 800 °C (for PbOPbO) and 300 to 700 °C (for PbO-SiO2). The results from microstructural observation showed that uniform, globular, non-wetting leadLead droplets formed on the surface of PbOPbO pellets. The leadLead droplets covered the whole surface, which appeared to inhibit further reduction. In the case of PbOPbO-SiO2, the viscous nature of the glass/slagSlag appeared to significantly hinder diffusion of hydrogenHydrogen within the pellet, resulting in a low reduction rate.