Current Photovoltaic Research ISSN:2288-3274(Print) 2508-125X(Online)

Lifetime of Si photovoltaics modules are about 25 years and a large amount of waste modules are expected to be discharged in the near future. Therefore, the extraction and collection of valuable metals out of discharged Si modules will be one of the important technologies. In this study, we demonstrated that supercritical CO₂ extraction method can be effectively used to remove Cu, one of the abundant elements in the module, as well as its oxide form, Cu₂O. Especially, we proved that the addition of hexane as co-solvent is effective for the removal of both materials. The optimal ratio of CO₂ and hexane was 4:1 at a fixed temperature and pressure of 250°C and 250 bar, respectively. In addition, it was proven that the removal of Cu₂O was preceded via reduction of Cu₂O to Cu.