Eco-friendly Approach of Silicon Recovery from Waste Silicon Photovoltaic Modules and Recycling of Silicon Powder

This paper presents an eco-friendly approach for reducing chemical solutions in the chemical process of recovering silicon from a silicon solar cell separated from a waste solar panel. Methanesulfonic acid or laser ablation was used to remove Ag metal electrodes instead of nitric acid. These processes can reduce the use of chemical acid solutions by 50% in our reference process consisting of nitric acid and hydrochloric acid. The purity of the recovered silicon powder measured by inductively coupled plasma atomic emission spectroscopy was more than 99.99% (4N). The feasibility of anode material for secondary batteries was tested by manufacturing recycled silicon powder and SiC powder using the recovered silicon. When the recovered silicon powder and high-purity silicon powder were mixed with the SiC powder, the initial capacity was 1256 mAh/g.