Fabrication and anodic polarization behavior of lead-based porous anodes in zinc electrowinning

A new type of lead-based porous anode in zinc electrowinning was prepared by negative pressure infiltration.The anodie polarization potential and corrosion rate were studied and compared with those of traditional fiat anodes (Pb-0.8%Ag) used in industry.The anode eorrosion rate was determined by anode actual current density and microstructure.The results show that the anodic oxygen evolution potential decreases first and then increases with the decrease of pore diameter.The anodic potential decreases to the lowest value of 1.729 V at the pore diameter of 1.25-1.60 mm.The porous anode can decrease its actual current density and thus decrease the anodic corrosion rate.When the pore diameter is 1.60-2.00 mm,the anodic relative corrosion rate reaches the lowest value of 52.1%.