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 effectiv...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.展开更多
The silicon organic polymer containing PSOT-3 （dioxothiocarbamide groups） has been synthesized and characterized, and the adsorption of Au（III） on PSOT-3 was investigated. The results showed that PSOT-3 had good a...The silicon organic polymer containing PSOT-3 （dioxothiocarbamide groups） has been synthesized and characterized, and the adsorption of Au（III） on PSOT-3 was investigated. The results showed that PSOT-3 had good adsorption capacity for Au（III）, and the adsorption of Au（III） was found to be the most effective in 0.1-0.3 mol/dm^3 hydrochloric acid solution. The adsorption is physical and the process is endothermic, and Freundlich isotherm fits the data better than the Langmuir isotherm. The adsorption can be generally described by electrostatic interaction （Coulomb＇s force） between the adsorbent and the adsorbate. The high adsorption capacity of this sorbent has significant potential for gold recovery from aqueous solutions.展开更多
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)
文摘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.
文摘The silicon organic polymer containing PSOT-3 （dioxothiocarbamide groups） has been synthesized and characterized, and the adsorption of Au（III） on PSOT-3 was investigated. The results showed that PSOT-3 had good adsorption capacity for Au（III）, and the adsorption of Au（III） was found to be the most effective in 0.1-0.3 mol/dm^3 hydrochloric acid solution. The adsorption is physical and the process is endothermic, and Freundlich isotherm fits the data better than the Langmuir isotherm. The adsorption can be generally described by electrostatic interaction （Coulomb＇s force） between the adsorbent and the adsorbate. The high adsorption capacity of this sorbent has significant potential for gold recovery from aqueous solutions.
