Title: The Rate of Boron Removal from Molten Silicon by CaO-SiO2 Slag and Cl2 Treatment
Abstract: Abstract In order to optimize a boron removal process by slag refining to obtain solar grade silicon, the rate of boron removal from molten silicon using CaO-SiO 2 slag was investigated at 1823 K in an Ar atmosphere. The rate of boron removal was found to be controlled by mass transfer in molten slags, and the mass-transfer coefficient of boron in molten slag in the present experimental condition was evaluated. Some experiments on chlorination of boron in silicon and that of borate in slag using Cl 2 gas were also carried out. Experimental results showed that the slag refining process with chlorination was proposed as a promising method for the boron removal from molten silicon.