Description
⌕ Enlarge Image
Zirconium is a transition metal that is a silvery white color in its natural solid state. Zirconium is resistant to corrosion, but it will ignite when exposed to air if it is in small, fine, amounts. Zirconium has an atomic weight of 91.224, a melting point of 3371 °F, and a boiling point of 7968 °F. The most common use of zirconium is as a component in fuel rods used in nuclear reactors; zirconium is also used as a component in some gems.
Isolation
Zirconium is never found free in nature, and isolation procedures are needed to extract zirconium from its mineral sources.
Zirconium occurs in over 30 different types of minerals, but the mineral that is used most often for isolating zirconium is zircon. Zircon can also be collected as a by product of titanium, tin, ilmenite, and rutile processing. The isolation procedure that is most often used to isolate zirconium from other minerals and elements is the Kroll process; during this process, zirconium chloride is reduced using magnesium metal.
The Kroll process is an industrial process that is mainly used to produce titanium through pyrometallurgical methods. During the zirconium isolation process, zirconium oxide is reacted with chlorine and carbon and heated to approximately 1652 °F. The result of this reaction is the formation of zirconium tetrachloride, iron trichloride, and carbon monoxide. The zirconium tetrachloride is separated from this mixture using fractional distillation producing zirconium chloride. The last step in the reaction involves combining zirconium chloride with magnesium and heating the mixture to 2012 °F. The end result is pure zirconium and magnesium chloride.