It is much easier removing impurities from the raw material for preparing metallurgical-grade silicon with ele...
LI Feng~1 XING Peng-Fei~(1,*) GUO Jing~(1,2) LIU Yang~1 TU Gan-Feng~1 (1 School of Materials and Metallurgy,Northeastern University,Shenyang 110004,China
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 efectively 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.
Peng-fei XingJing GuoYan-xin ZhuangFeng LiGan-feng Tu
