Thermal Plasma Synthesis of Silicon Carbide From Solar Waste Panels

Abstract

Thermal plasma systems are used to recover essential elements from sophisticated end-of-life (EOL) electronic components. The photovoltaic (PV) industry has undergone rapid development, resulting in an increasing quantity of silicon (Si)-based solid waste (SIBS), and is considered the most difficult waste to handle for recycling. In this study, we have implemented a novel pathway for transforming solar waste panels (containing 35% Si) and compact disk s (CDs containing 20% carbon) into an advanced hybrid material by high-temperature carbothermal reduction (around 1600 °C–1700 °C) using sustainable thermal plasma arc technology. The benefit of the thermal plasma technique is that it is an environmentally friendly, single-step process that is scalable compared to other carbothermic methods and chemical routes. The pure phases of Si and silicon carbide (SiC) were confirmed using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). This study also involved the development of an Al-Si-SiC metal matrix composite (MMC) by gravity casting, using a combination of Silicon carbide (SiC), Silicon (Si), and Aluminium alloy (Al). Hardness is remarkably improved from 56 to 76 Brinell hardness number (BHN) compared to existing Al alloy. The thermal conductivity of the composite showed remarkable improvement, 126 W/ m⋅K , compared with the existing Al alloy. This innovative approach of using solar waste as resources is an alternative for materials synthesis of silicon carbide and also reduces the dependency on traditional raw materials.