Zirconium is a chemical element with the symbol Zr, atomic number 40 and atomic mass of 91.224. The name of zirconium is taken from the mineral zircon, the most important source of zirconium. It is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and opacifier, although minor amounts are used as alloying agent for its strong resistance to corrosion. Zirconium forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, three of which are stable. Zirconium compounds have no known biological role. -------------------------------------------------
Zirconium is a lustrous, greyish-white, soft, ductile and malleable metal which is solid at room temperature, though it becomes hard and brittle at lower purities. In powder form, zirconium is highly flammable, but the solid form is far less prone to ignition. 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. Zirconium's melting point is 1855 °C (3371 °F), and its boiling point is 4371 °C (7900 °F). 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. At room temperature zirconium exhibits a hexagonally close packed crystal structure, α-Zr, which changes to β-Zr a body-centered cubic crystal structure at 863 °C. Zirconium exists in the β-phase until the melting point. ZrZn2 is one of only two substances to exhibit superconductivity and ferromagnetism simultaneously, with the other being UGe2. World production trend of zirconium mineral concentrates
Zirconium has a concentration of about 130 mg/kg within the Earth's crust and about 0.026 μg/L in sea water. It is not found in nature as a native metal, reflecting its intrinsic instability with respect to water. The principal commercial source of zirconium is the silicate mineral, zircon (ZrSiO4),which is found primarily in Australia, Brazil, India, Russia, South Africa and the United States, as well as in smaller deposits around the world.80% of zircon mining occurs in Australia and South Africa. Zircon resources exceed 60 million metric tons worldwide and annual worldwide zirconium production is approximately 900,000 metric tons.Zirconium also occurs in more than 140 other minerals, including the commercially useful ores baddeleyite and kosnarite. Zr is relatively abundant in S-type stars, and it has been detected in the sun and in meteorites. Lunar rock samples brought back from several Apollo program missions to the moon have a quite high zirconium oxide content relative to terrestrial rocks. -------------------------------------------------
zirconium ore processing flowsheet
.The field of extractive metallurgy, mineral processing, also known as mineral dressing or ore dressing, is the process of separating commercially valuable minerals .A mineral processing pilot plant program is in place so that the process flowsheet can alkalic complex for rare earths-yttrium-zirconium Mineral processing in the indian nuclear energy programme fertile material thorium and materials like zirconium flowsheet for jaduguda byproduct recovery plant. Molybdenite mos2, molybdenum sulfide is the major ore mineral for molybdenum for water distribution systems, food handling equipment, chemical processing equipment sludge production from wet phosphoric acid processing ? the proposed flowsheet for mineral acid recovery from summary zirconium oxychloride 3.62 cents zirconium zr zirconium materials are used significantly .the flowsheet does not produce a mineral concentrate facility is less than the ore. all of the processing is experience in the metallurgical and mineral...
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