Potassium hexafluorozirconate

Fluorozirconate Crystallization. Repeated dissolution and fractional crystallization of potassium hexafluorozirconate was the method first used to separate hafnium and zirconium (15), potassium fluorohafnate solubility being higher. This process is used in the Prinieprovsky Chemical Plant in Dnieprodzerzhinsk, Ukraine, to produce hafnium-free zirconium. Hafnium-enriched (about 6%) zirconium hydrous oxide is precipitated from the first-stage mother Hquors, and redissolved in acid to feed ion-exchange columns to obtain pure hafnium (10). 

Fluorosilicate Fusion. The fusion reaction of milled zircon with potassium hydrogen fluoride was used to prepare potassium hexafluorozirconate [16923-95-8] for studies leading to the first separation of hafnium and zirconium (30). Similar reactions using potassium hexafluorosihcate have been used (31,32) commercially in the United States and the former USSR ... 

The use of potassium hexafluorosihcate is preferred over sodium hexafluorosihcate because of the lower tendency of the potassium compound to dissociate the lose sihcon tetrafluoride by sublimation. The addition of potassium carbonate or chloride to the fusion mix further reduces this tendency and promotes completion of the reaction. The reaction is conducted in a rotary furnace operating at 700°C. The product is cmshed prior to leaching with acidified hot water. The hot slurry is filtered to remove the sihca, and potassium hexafluorozirconate crystallizes as the solution cools. 

Potassium hexafluorozirconate (K2ZrF6) is leached with hot 1% hydrochloric acid. The hafnium present in the ore undergoes a similar reaction, forms potassium hexafluorohafnate (K2HfF6), and enters the solution during leaching. These two compounds, K2ZrF6 and... 

Zirpro A process for flame-proofing textiles by treating them with aqueous solutions of zirconium complexes. Wool is treated with aqueous potassium hexafluorozirconate and citric acid. Developed by the International Wool Secretariat, Yorkshire, now based in Melbourne, Australia. 

Fluorosilicate Fusion. Milled zircon and potassium hexafluorosflicate are heated together to yield potassium hexafluorozirconate and silica... 

The fused product is cooled, cmshed, and leached with acidified hot water. The resulting hot solution of potassium hexafluorozirconate—hafnate is filtered to remove silica, then cooled to allow crystallization of the potassium hexafluorozirconate—hafnate. Many of the impurity metals remain in solution. 

Aflammit ZR Dipotassium hexafluorozirconate(2-) Dipotassium zirconium hexafluoride EINECS 240-985-6 HSDB 2019 NSC 310011 Potassium fluorozirconate Potassium fluorozirconate (K2ZrF6) Potassium hexafluorozirconate Potassium zirconifluoride Potassium zirconium fluoride Potassium zirconium hexafluoride Zirconate(2-), hexafluoro-, dipotassium Zirconium potassium fluoride, Flameprooflng agent used in wool processing. Also used in manufacture of zirconium. Solid slightly soluble in cold H2O, Thor Chemicals (UK) Ltd. 

Potassium Hexafluorozirconate [16923-95-8]. This water-soluble com-poimd is a flame retardant for wool by the Zirpro process. Applied in combination with formic acid and citric acid, the fluorozirconate exhausts onto wool and after mild heating, provides a fairly wash-dimable flame-retardant finish. Wool upholstery for aircraft makes use of this treatment (19). 

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