Towards a viable method of reusing silicon carbide. Physicochemical analyses in the studies on industrial application of the material

Abstract

The paper presents an investigation on the feasibility of recovery of the highly valuable silicon carbide (SiC) from the slurry waste generated from silicon wafer production in the photovoltaic and semiconductor industry. Compared to the other techniques of recycling, a facile and low-cost method of waste treatment via heat drying followed by low-energy mixing in a shaker mixer was proposed. As the result of the treatment, the slurry waste was converted into a powdered form with dominant content of SiC. Separated SiC material was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, and sieve analysis. In addition, analyses of the bulk density, moisture content and melting test were carried out. As was confirmed by the physicochemical analyses, the dominant sieve fraction was in the range of 0.1-0.06 mm, the purity level was a minimum 99% mass of SiC, the moisture content -0.3%, the bulk density -1.3 g/cm 3 . The physicochemical characteristics of the material were crucial for understanding the material performance, assessment of the material quality and determining the perspective directions of the industrial application. The studies revealed that the material exhibited a high application potential as abrasive, especially in abrasive grinding and waterjet cutting.