Rapid recovery of polycrystalline silicon from kerf loss slurry using double-layer organic solvent sedimentation method  

作　　者：Peng-fei Xing Jing Guo Yan-xin Zhuang Feng Li Gan-feng Tu 

机构地区：[1]School of Materials and Metallurgy,Northeastern University [2]Xinjiang Joinworld Co., Ltd.,Xinjiang Uygur Autonomous Region [3]Key Laboratory of Electromagnetic Processing of Materials,Northeastern University

出　　处：《International Journal of Minerals,Metallurgy and Materials》2013年第10期947-952,共6页矿物冶金与材料学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.51074043);the National Key Technology R&D Program(No.2011BAE03B00);the Fundamental Research Funds for the Central Universities(No.N120409004)

摘　　要：The rapid development of photovoltaic （PV） industries has led to a shortage of silicon feedstock. However, more than 40% silicon goes into slurry wastes due to the kerf loss in the wafer slicing process. To effectively recycle polycrystalline silicon from the kerf loss slurry, an innovative double-layer organic solvent sedimentation process was presented in the paper. The sedimentation velocities of Si and SiC particles in some organic solvents were investigated. Considering the polarity, viscosity, and density of solvents, the chloroepoxy propane and carbon tetrachloride were selected to separate Si and SiC particles. It is found that Si and SiC particles in the slurry waste can be successfully separated by the double-layer organic solvent sedimentation method, which can greatly reduce the sedimentation time and improve the purity of obtained Si-rich and SiC-rich powders. The obtained Si-rich powders consist of 95.04% Si, and the cast Si ingot has 99.06% Si.The rapid development of photovoltaic （PV） industries has led to a shortage of silicon feedstock. However, more than 40% silicon goes into slurry wastes due to the kerf loss in the wafer slicing process. To effectively recycle polycrystalline silicon from the kerf loss slurry, an innovative double-layer organic solvent sedimentation process was presented in the paper. The sedimentation velocities of Si and SiC particles in some organic solvents were investigated. Considering the polarity, viscosity, and density of solvents, the chloroepoxy propane and carbon tetrachloride were selected to separate Si and SiC particles. It is found that Si and SiC particles in the slurry waste can be successfully separated by the double-layer organic solvent sedimentation method, which can greatly reduce the sedimentation time and improve the purity of obtained Si-rich and SiC-rich powders. The obtained Si-rich powders consist of 95.04% Si, and the cast Si ingot has 99.06% Si.

关 键 词：silicon PURIFICATION SEDIMENTATION organic solvents waste utilization 

分 类 号：TN304.12[电子电信—物理电子学]