Zircon alkali fusion

Zircon Alkali fusion at 600 °C ZrSi04 + 4 NaOH —> Na2Zr03 + Na2Si03 + 2 H20 Water leaching... 

Zirconium oxide, Zr02 is widely known, both as a mineral, baddeleyite, and as an industrial product obtained horn zircon, Z1SO4. Moreover, the precipitate obtained by action of alkali hydroxides upon solutions of tetravalent zirconium is a hydrated oxide. The latter is readily soluble in acids to form oxysalts, which arc usually formulated in terms of the Zr02+ ion, without including its water of hydration, e.g., as Zr0(H2P04)2. The hydrated Zr02+ ion is not amphiprotic it does not dissolve in alkali hydroxides, While it does react on alkali carbonate fusions, the compounds formed have been shown to be mixed oxides rather than zirconates. 

Fusion with alkali hydroxides converts Zr02 to a zirconate ... 

Pure zirconia is obtained via the chlorination and thermal decomposition of zirconia ores, their decomposition with alkali oxides, and lime fusion. The initial stage of the process is based on the chlorination of zircon in the presence of carbon at a temperature of 800-1200 °C in a shaft furnace ... 

The oxide of pure zirconium (Zirconia = Zr02) is obtained from sands of zircon (ZrSi04) or baddeleyite (Zr02) by a chemical processes via of chlorination and thermal decomposition, alkali oxide decomposition or lime fusion or by plasma decomposition [30],... 

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