Recent progress in upgrading metallurgical-grade silicon to solar-grade silicon via pyrometallurgical routes  

作　　者：Yun Lei Xiaodong Ma Ye Wang Zhiyuan Chen Yongsheng Ren Wenhui Ma Kazuki Morita 

机构地区：[1]Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China [2]Sustainable Minerals Institute,The University of Queensland,St Lucia 4072,QLD,Australia [3]School of Chemical Engineering,Sichuan University,Chengdu 610065,China [4]Separation and Conversion Technology,Flemish Institute for Technological Research,Mol 2400,Belgium [5]Department of Materials Engineering,Graduate School of Engineering,The University of Tokyo,Tokyo 113-8656,Japan

出　　处：《International Journal of Minerals,Metallurgy and Materials》2022年第4期767-782,共16页矿物冶金与材料学报（英文版）

摘　　要：Si-based photovoltaic solar power has been rapidly developed as a renewable and green energy source.The widespread use of Sibased solar cells requires large amounts of solar-grade Si(SoG-Si)to manufacture Si wafers.Chemical routes,mainly the modified Siemens process,have dominated the preparation of polycrystalline SoG-Si;however,traditional chemical techniques employ a series of complex chemical reactions involving various corrosive and hazardous reagents.In addition,large amounts of complex waste solar cells and Si kerf slurry waste gradually accumulate and are difficult to recycle using these approaches.New methods are required to meet the demand for SoGSi preparation and Si waste recycling.The metallurgical route shows promise but is hindered by the problem of eliminating B and P from metallurgical-grade Si(MG-Si).Various pyrometallurgical treatments have been proposed to enhance the removal of B and P from MG-Si.This article reviews Si refining with slag treatment,chlorination,vacuum evaporation,and solvent refining,and summarizes and discusses the basic principles and recent representative studies of the four methods.Among these,solvent refining is the most promising and environmentally friendly approach for obtaining low-cost SoG-Si and is a popular research topic.Finally,a simple and green approach,i.e.,a combination of solvent refining,slag treatment,or vacuum directional solidification,is proposed for low-cost SoG-Si preparation using MG-Si or Si wastes as raw materials.

关 键 词：silicon refining solar-grade silicon solvent refining vacuum evaporation slag treatment Si kerf slurry waste 

分 类 号：TQ127.2[化学工程—无机化工] TM914.4[电气工程—电力电子与电力传动]