SiC Powder Manufacturing through Silicon Recovery from Waste Si Solar Cells

Abstract

We recovered Si from the waste Si solar cell through a three-stage chemical process at room temperature and recycled the recovered Si to investigate the manufacture of SiC particles. Metal electrodes made of Ag and Al were removed using either nitric acid solution or hydrochloric acid solution. After etching the metal electrodes, the anti-reflection coatings containing SiNx and SiOx were removed by employing a mixed solution of NH 4 HF 2 , H 2 O 2 , and H 2 SO 4 . Small quantities of impurities remaining in the Si solar cells were subsequently removed through the application of potassium hydroxide to recover Si. Based on the measurements conducted through inductively coupled plasma atomic emission spectroscopy, the purity of the recovered Si was found to be 99.99% (4N), and no high energy-consuming steps were involved in the proposed chemical process. Furthermore, by incorporating the 4N purity-grade Si, we successfully obtained SiC particles for usage in structural ceramic materials. This suggests that the proposed chemical process can aid in recycling recovered Si.

A Study on the Recovery of Valuable Metals from Solar Cells Using Acid Leaching and Substitution Reactions

“…This market expansion has allowed it to produce electricity at a much lower price than other energy production methods in regions with favorable climatic conditions [4]. However, the lifetime of solar modules is 20-30 years, and most of the modules that were initially installed have reached the end of their lifespan and are currently being partially scrapped and demolished [5,6]. The generation of waste solar modules is expected to exceed 1.7 million tons after 2030 [6][7][8][9].…”

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

“…따라서 사용된 화학약품 비용 및 폐액 처리 비용 등이 많이 발생되고 있어 이에 대한 사용량 감소 및 효율적인 처리 방안이 요구된다. 이전에 보고된 바와 같이 4) , 실리콘 회수 공정은 주로 질산(HNO 3 ), 염 산(HCl), 황산(H 2 SO 4 ), 수산화칼륨(KOH) 수용액을 사용하여 총 4단계에 걸쳐 제거 대상층을 제거한다. 2Ag 회수된 실리콘의 SiC분말 제조는 ㈜플러스 매니저의 도움을 받아 진행하였습니다.…”