Separation of Cu, Sn, Pb from photovoltaic ribbon by hydrochloric acid leaching with stannic ion followed by solvent extraction

Abstract

A recycling process consisting of HCl leaching with Sn4 + followed by solvent extraction is proposed to recover Cu, Sn and Pb from photovoltaic (PV) ribbon. During HCl leaching with Sn4 +, Sn and Pb were removed from PV ribbon whereas Cu remained as plate. The leaching efficiency of Sn increased with increasing temperature, initial Sn4 + concentration or decreasing pulp density. In the case of leaching test performed in the 1 M HCl solution at 400 rpm and 70 °C with 5% pulp density and 5000 mg/L Sn4 +, the leaching efficiency of Sn increased to > 99% within 60 min, whereas 71.9% of Pb was recovered as PbCl2 powder after settling the leach solution for 24 h at room temperature. A solvent extraction with tri-butyl phosphate (TBP) was performed to extract selectively Sn from leach solution. The extraction efficiency of Sn increased with increasing the contents of TBP in kerosene, and < 1% of Pb was extracted. Therefore, the separation of Sn, Cu, Pb was achieved successfully by the recycling process.