Baddeleyite ZrO

Zirconium oxide (ZrO ) is the most common compound of zirconium found in nature. It has many uses, including the production of heat-resistant fabrics and high-temperature electrodes and tools, as well as in the treatment of skin diseases. The mineral baddeleyite (known as zirconia or ZrO ) is the natural form of zirconium oxide and is used to produce metallic zirconium by the use of the Kroll process. The KroU process is used to produce titanium metal as well as zirconium. The metals, in the form of metaUic tetrachlorides, are reduced with magnesium metal and then heated to red-hot under normal pressure in the presence of a blanket of inert gas such as helium or argon. 

Finally, it may also be pointed out that the structure of baddeleyite itself may be described in a similar manner very shghtly distorted (100) unit layers of fluorite-type (ZrO layers of edge-shared OZt4 tetrahedra) alternate with commensurate 3 4 3 4 layers of anions. Small rotations of the triangles in the latter convert 3 4 3 4 to 3 (the anion-only layers in Y 0 iF 4.2) similarly, small rotations of the squares convert 3 4 3 4 to 4 (the anion-only layers in the fluorite type) . ... 

Pure Grade ZrO. from Donetsk Plant of Chemical Reagents Properties (acid-washed) baddeleyite, particle size 2-20 pm, BET specific surface area 20 m /g [2182]. 

One of the features of Zr breakdown emission is strong Zr III and Zr IV emissions (Gaft et al. 2013) (Fig. 8.39a) and characteristic molecular emission of ZrO (Fig. 8.39b), which may be effectively used for analytical purposes, especially when high contents of Fe takes place in the analyzed material. For example, unique Fe-P deposit in Cola Peninsula (Russia) accompanied by high levels of baddeleyite (Fig. 8.39c). 

Figures 1.4(a) and 1.4(b) show parts of the baddeleyite-type structure of zirconium dioxide ZrO. This structure belongs to the monoclinic space group P2i/c and has a distorted fluorite-type structure. The coordination number (CN) of the Zr cations is seven, which is smaller than that of the fluorite-type oxide (CN = 8). This smaller value (CN = 7) is attributable to the smaller size of Zr cations ( (Zr + s) = 0.84 A) compared to the criterion deduced from Pauling s first rule (r( >8) 1.079 A) for A cations with a CN of eight...

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