Dissociation equilibria of tungstate ion in a molten fluoride and the effect on electrodeposition

Article abstract of DOI:10.1149/1.2086791

The dissociation equilibria of tungstate ion in a molten fluoride system have been investigated using a zirconia-air oxide ion indicator. The dissociation constant, K, of the reaction in molten LiF-KF eutectic at 973 K has been determined to be K = 5(±1) × 10^-12 (mole fraction unit). With this taken into consideration, tungsten has been electrodeposited from molten LiF-KF-K₂WO₄ under several sets of electrolytic conditions, with addition of small amounts of Na₂O. The texture of the electrodeposit was nodular or mossy, the surface becoming rougher with increasing concentration of oxide ion (up to about 0-3 × 10^-3 mole fraction). When the oxide ion concentration in the molten fluoride was high (1 × 10^-2mole fraction), however, the surface of the electrodeposit became uniform.

Full text of DOI:10.1149/1.2086791

Downloaded on 2015-03-10 to IP 130.126.162.126 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-03-10 to IP 130.126.162.126 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-03-10 to IP 130.126.162.126 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-03-10 to IP 130.126.162.126 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).

Downloaded on 2015-03-10 to IP 130.126.162.126 address. Redistribution subject to ECS terms of use (see ecsdl.org/site/terms_use) unless CC License in place (see abstract).