| 20090263307 | Silicon Production Process - An improved process for producing high purity silicon results from the reaction of sodium with pure silicon tetrafluoride gas, which produces sodium fluoride as a by-product. The silicon tetrafluoride gas is formed by decomposing sodium fluorosilicate. The sodium fluorosilicate is produced by precipitation when fluorosilicic acid (FSA) is reacted with the by-product sodium fluoride in closed loop process. Likewise, the fluorosilicic acid is preferably formed at high purity using a source material that consists essentially of silica by reacting the by-product sodium fluoride with an acid to create reactive fluoride ions. | 10-22-2009 |
