Fluoride glasses: zirconium-based

Except for BeF2, glasses based on divalent fluorides show a broader IR transparency than glasses based on indium or zirconium, as reported for ZnSB and ZnSBC in Fig. 1 [10]. They exhibit a full transparency up to 9 /an for the former and 10 nm for the latter which is a pure MF2 fluoride glass containing Zn, Sr, Ba, and Cd. 

The optical properties of Pr3+ ions have been studied in various fluoride glasses based on zirconium [31,43,45-47], on indium [31,43,48,49] or on zinc fluorides [48,50]. 

Erbium ions in fluoride glasses possess several radiative transitions from the violet to the mid-IR (3.45 pm) as shown in Fig. 10. Their spectroscopic parameters such as radiative lifetimes and branching ratios were determined for several types of glasses based on zirconium, indium, aluminum or even zinc fluoride [31,98-100]. 

Zirconium-silicate refractories have found successful application in certain parts of glass furnaces, in particular those for borosilicate and fluoride glasses (tank, feeder, throat). Refractories based on Cr203 have recently been employed at the critical points of glass tanks. This oxide show s the best resistance to glass-contact corrosion but its application is limited by its colouring effect. 

Zirconium tetrafluoride [7783-64-4] is used in some fluoride-based glasses. These glasses are the first chemically and mechanically stable bulk glasses to have continuous high transparency from the near uv to the mid-k (0.3—6 -lm) (117—118). Zirconium oxide and tetrachloride have use as catalysts (119), and zirconium sulfate is used in preparing a nickel catalyst for the hydrogenation of vegetable oil. Zirconium 2-ethyIhexanoate [22464-99-9] is used with cobalt driers to replace lead compounds as driers in oil-based and alkyd paints (see Driers and metallic soaps). 

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