Production, Chemical Properties, Occurrence
Zirconia is produced by calcining zirconium compounds, exploiting its high thermal stability.
Unlike TiO2, which features octahedral Ti in all phases, zirconia consists of seven-coordinate zirconium centres. This difference is attributed to the larger size of Zr atom relative to the Ti atom.
Zirconia is relatively unreactive chemically. It is attacked by fluoride and alkalis. When heated with carbon, it converts to zirconium carbide. When heated with carbon in the presence of chlorine, it converts to zirconium tetrachloride. This conversion is the basis for the purification of zirconium metal and is analogous to the Kroll process.
Aside from baddeleyite, another naturally occurring form of ZrO2 is the very rare cubic mineral tazheranite (Zr,Ti,Ca)O2 (and a doubtful mineral arkelite).
Read more about this topic: Zirconium Dioxide
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