Removal of Boron from Silicon-Tin Solvent by Slag Treatment |
| |
Authors: | Xiaodong Ma Takeshi Yoshikawa Kazuki Morita |
| |
Affiliation: | 1. Institute of Industrial Science, The University of Tokyo, Tokyo, 153-8505, Japan 2. School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia
|
| |
Abstract: | To eliminate B effectively from Si for its use in a solar cell, a novel process involving the slag refining of molten Si with Sn addition was investigated. The partition ratio of B between CaO-SiO2-24 mol pct CaF2 slag and Si-Sn alloy at 1673 K (1400 °C) was determined by the chemical equilibrium technique. It was found that the partition ratio of B was remarkably increased with the increase in Sn content of alloy, which attributes to the increase in activity coefficient of B as well as the oxygen partial pressure. The partition function was accounted as much as 200 when the alloy composition was Si-82.4 mol pct Sn, which was much higher than the reported values in the range of 1 to 3. The required amounts of slag used for B removal from Si-30, 50, and 70 mol pct Sn melts were only 15.6 pct, 6.5 pct, and 1.2 pct of that used for the removal of B directly from MG-Si without Sn addition in a single slag treatment. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|