Guide to Zirconium and Zirconium Compounds
Zirconium (Zr) and Zirconium Compounds for Sale
Zirconium is a chemical element with the symbol Zr and atomic number 40. It is a lustrous, gray-white, strong transition metal that resembles titanium. Zirconium is never found as a native metal, but is instead obtained mainly from the mineral zircon. Zirconium is used as an alloying agent due to its high resistance to corrosion.
Zirconium is a lustrous, grayish-white, soft, ductile, and malleable metal which is solid at room temperature, though it becomes hard and brittle at higher purities. In powder form, zirconium is highly flammable, but the solid form is far less prone to igniting. Zirconium is highly resistant to corrosion by alkalis, acids, salt water, and other agents. However, it will dissolve in hydrochloric and sulfuric acid, especially when fluorine is present. Alloys with zinc become magnetic below 35 K. The melting point of zirconium is at 1855°C, and the boiling point is at 4409°C. Zirconium has an electronegativity of 1.33 on the Pauling scale. Of the elements within d-block, Zirconium has the fourth lowest electronegativity after yttrium, lutetium, and hafnium.
Because of Zirconium’s excellent resistance to corrosion, it is often used as an alloying agent in materials that are exposed to corrosive agents, such as surgical appliances, explosive primers, vacuum tube getters and filaments. Zirconium dioxide (ZrO2) is used in laboratory crucibles, metallurgical furnaces, and as a refractory material. Zircon (ZrSiO4) is cut into gemstones for use in jewelry. Zirconium carbonate (3ZrO2·CO2·H2O) was used in lotions to treat poison ivy, but this was discontinued as it caused bad skin reactions in some cases. 90% of all zirconium produced is used in nuclear reactors because of its low neutron-capture cross-section and resistance to corrosion. Zirconium alloys are used in space vehicle parts for their resistance to heat, an important quality given the extreme heat associated with atmospheric reentry.
As a transition metal, zirconium forms various inorganic compounds, such as zirconium dioxide (ZrO2). This compound, also referred to as zirconia, has exceptional fracture toughness and chemical resistance, especially in its cubic form. These properties make zirconia useful as a thermal barrier coating, though it is also a common diamond substitute. Zirconium tungstate is an unusual substance in that it shrinks in all directions when heated, whereas other elements expand when heated. Other inorganic zirconium compounds include zirconium (II) hydride, zirconium nitride, and zirconium tetrachloride (ZrCl4), which is used in the Friedel-Crafts reaction. Organozirconium chemistry is the study of compounds containing a carbon-zirconium bond. These organozirconium compounds are often employed as polymerization catalysts. The first such compound was zirconocene dibromide, prepared in 1952 by John M. Birmingham at Harvard University. Schwartz’s reagent, prepared in 1970 by P. C. Wailes and H. Weigold, is a metallocene used in organic synthesis for transformations of alkenes and alkynes.