Stage recycling of solar panels by pyrolysis and vacuum-free electric arc conversion to produce SiC

The rapid growth in the number of solar panels worldwide is making the issue of their utilization increasingly urgent. This paper presents a combined approach to recycling spent solar panels. The polymeric components were processed by pyrolysis to produce carbon residue and synthesis gas, while the inorganic components underwent plasma treatment to produce silicon carbide (SiC). Pyrolysis at 500°C produced synthesis gas containing up to 5 vol.% methane, as well as carbon monoxide (CO) and carbon dioxide (CO₂), with maximum concentrations of up to 0.6 vol.%. The average yield of carbon residue was 45.8 wt.%. Vacuum-free electric arc treatment ensured the synthesis of silicon carbide. According to X-ray phase analysis, increasing the carbon content of the mixture from 0% to 30% resulted in an increase in the SiC fraction from 46% to 61%, while the fractions of free silicon and silicon oxide decreased simultaneously. This approach not only ensures efficient management of solar panel waste but also enables the recovery of useful resources for further utilization.