| 초록 |
Since solar modules have a life span of about 25 years, a large amount of waste modules will be discharged in the future and how to handle them is a problem. Most of the metal in the solar module is dependent on imports. Especially, if imported metals and silicon recovery technologies are developed from solar cells, which are in increasing demand, import substitution is expected, which is essential technology for strengthening competitiveness in renewable energy sector. In this study, we used supercritical fluid extraction as a recycling method for waste modules. Supercritical fluids are characterized by the simultaneous manifestation of gas and liquid properties when the temperature and pressure above the critical point are applied. The solubility of the supercritical fluid changes with temperature and pressure above the critical point. 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℃ and 250 bar, respectively. In addition, it was proven that the removal of Cu2O was preceded via reduction of Cu2O to Cu |
