![]() It is specially purified to remove hafnium, which absorbs neutrons much more readily. It is well suited for this purpose because it is corrosion resistant and does not readily absorb thermal neutrons. It is employed in tubes for cladding uranium oxide fuel. A major use of the metal is in nuclear reactors. The metal also has many other uses, among them in photographic flashbulbs and surgical instruments, in the removal of residual gases from electronic vacuum tubes, and as a hardening agent in alloys, especially steel. Zirconium compounds also have minor uses as catalysts, in the dye, textile, plastics, and paint industries, and in pharmaceuticals such as poison ivy lotions. It occurs in nature as the silicate (ZrSiO 4) and is used as a gemstone it may be clear or colored, and is usually called zircon or hyacinth. The most important compound is the oxide zirconia (ZrO 2), used extensively as a refractory material in furnaces and crucibles, in ceramic glazes, and, formerly, in gas mantles. It forms a number of compounds, among them zirconate (ZrO 3 −2) and zirconyl (ZrO +2) salts. Zirconium is extremely resistant to heat and corrosion. Its chemical and physical properties are similar to those of titanium, the element above it in Group 4 of the periodic table. At ordinary temperatures it has a hexagonal close-packed crystalline structure. Zirconium is a very strong, malleable, ductile, lustrous silver-gray metal. While aquatic plants have a rapid uptake of soluble zirconium, land plants have little tendency to adsorb it, and indeed 70% of plants that have been tested showed no zirconium to be present at all.Zirconium zərkō´nēəm, metallic chemical element symbol Zr at. Zirconium is unlikely to present a hazard to the environment. It is among the long-lived radionuclides that have produced and will continue to produce increased cancers risk for decades and centuries to come. Zirconium 95 is one of the radionuclides involved in atmospheric testing of nuclear weapons. Most passes through the gut without being adsorbed, and that which is adsorbed tends to accumulate slightly more in the skeleton than in tissue. The estimated dietary intake is about 50 microg. Zirconium and its salts generally have low systemic toxicity. Australia, South Africa, India, Sri Lanka and the USA have vast deposits of zircon and zirconia sands. ![]() The estimated reserves exceed a billion tonnes. World production is in excess of 900.000 tonnes per year of zircon, and 7000 tonnes of the metal are produced. The chief ores are zircon (ZrSiO4), which is mined in Australia, USA and Sri Lanka, and baddeleyite (Zirconium oxide ZrO2) which is mined in Brasil. Zirconium is more than twice as abundant as copper and zinc and more than 10 times more abundant than lead. Zirconium is not a particularly rare element but because its most common mineral, zircon, is highly resistant to weatering it is only slightly mobile in the environment. The paper and packaging industries are finding that zirconium compounds make good surface coatings because they have excellent water resistance and strength. The metal also has many other uses, among them in photographic flashbulbs and surgical instruments, to make the glass for television, in the removal of residual gases from electronic vacuum tubes, and as a hardening agent in alloys, especially steel. Zircon is also marketed as a natural gemstone used in jewelry. The major end uses of zircon (ZrSiO 4) are refractories, ceramic opacification and foundry sands. Baddeleyite and impure zirconium (zirconia) are used in lab crucibles. Also used in catalytic converters, percussion caps and furnace bricks. Zirconium is used in alloys such as zircaloy, which is used in nuclear applications since it does not readily absorb neutrons. Zirconium does not dissolve in acids and alkalis. Zirconium powder is black and is regarded as very dangerous fire hazard. When it is finely divided, the metal can spontaneously ignite in air, especially at high temperatures. Zirconium is lighter than steel and its hardness is similar to copper. Its chemical and physical properties are similar to those of titanium. ![]() Zirconium - Zr Chemical properties of zirconium - Health effects of zirconium - Environmental effects of zirconium Separation and Concentration Purification Request.Plant Inspection & Process Optimalisation.
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