Generating SiF4 From H2SiF6

Sodium and barium fluorosilicates precipitated and thermally decomposed into silicon tetrafluoride. Barium fluorosilicate thermally decomposes at lower temperatures in shorter times, to give same percentage yield of silicon tetrafluoride gas, than sodium fluorosilicate. Salt byproducts of decompositions recycled to precipitate fluorosilicates from hexafluorosilicic acid, the primary reactant.