Purification and preparation of pure SiC with silicon cutting waste

• Published in: Journal of environmental management Vol. 363; p. 121364
• Main Authors: Jiang, Shengnan, Wang, Yilong, Zhang, Baojie, Xu, Xiaoxu, Gao, Shuaibo
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2024
• Subjects: Iron leaching; Kinetics analysis; Silicon carbide; Silicon cutting waste; Ultrasonic leaching; Ultrasonic leaching; Iron leaching; Silicon carbide; Kinetics analysis; Silicon cutting waste
• ISSN: 0301-4797; 1095-8630; 1095-8630
• DOI: 10.1016/j.jenvman.2024.121364

Recycling silicon cutting waste (SCW) plays a pivotal role in reducing environmental impact and enhancing resource efficiency within the semiconductor industry. Herein SCW was utilized to prepare SiC and ultrasound-assisted leaching was investigated to purify the obtained SiC and the leaching factors were optimized. The mixed acids of HF/H2SO4 works efficiently on the removal of Fe and SiO2 due to that HF can react with SiO2 and Si and then expose the Fe to H+. The assistance of ultrasound can greatly improve the leaching of Fe, accelerate the leaching rate, and lower the leaching temperature. The optimal leaching conditions are HF–H2SO4 ratio of 1:3, acid concentration of 3 mol/L, temperature of 50 °C, ultrasonic frequency of 45 kHz and power of 210 W, and stirring speed of 300 rpm. The optimal leaching ratio of Fe is 99.38%. Kinetic analysis shows that the leaching process fits the chemical reaction-controlled model. •1.Pure SiC was prepared with silicon cutting waste and ultrasonic-assisted acid leaching.•The mixed acids of HF/H2SO4 works efficiently on the removal of Fe and SiO2.•Ultrasound greatly improves the leaching of Fe from silicon cutting waste.