Zirconium Facts

Placed in the 40th position in the Periodic table, symbolized as 'Zr', a lustrous, gray-white, strong transition metal is a chemical element known as Zirconium. Martin Heinrich Klaproth discovered its existence in the year 1789, in a stone which was brought to him from island of Ceylon (now Sri Lanka).

This element, as mentioned, has an atomic number of 40 and atomic mass of 91.224 amu (atomic mass unit). Its melting point is 1855 °C and boiling point is 4409 °C.

• Australia, Brazil, India, Russia and the USA are the major locations where zirconium deposits are found.
• It is abundant in S-type stars and its existence has also been detected in the Sun and the meteorites.

• The abundance of this metal in lunar rock samples has been found to be higher than what is found in terrestrial rocks.
• As a transition metal, zirconium is a good conductor of heat and fire. It also scores well on malleability and ductility.
• The metal has an atomic radius (pm) of 160 and Ionic radius of 790(+4e).

• Its lattice structure is hexagonal, and it has a lattice constant of 3.230.
• Specific heat is 0.281 @20°C J/g mol, and fusion heat is 19.2 (kJ/mol).
• Zirconium in powder form is highly susceptible to combustion, however, far less when in solid form.

• Alkalis, acids, salt water and many other agents have no corrosive effects on zirconium. However, if combined with hydrochloric and sulfuric acid, it will dissolve. This reaction becomes faster in the presence of fluorine.

• Inhalation of the compounds of this metal may cause skin and lung granulomas (a tumor composed of granulation tissue resulting from injury or inflammation or infection). Minor skin irritation has also been reported due to contact with zirconium powder. If it comes in contact with eyes, then it may warrant medical attention.

• The metal attains the property of a superconductor [a conductor that offers zero resistance to current; for this it must attain a certain temperature called the "critical temperature"] when alloyed with niobium (soft, gray, ductile transition metal).
• Zirconium has a Pauling negativity number of 1.33.

• The metal shares similar properties with titanium. However, the former has higher density and melting temperature than that of the latter.

Having discussed some basic facts on zirconium, now let us know about some common uses of the metal.

# Zirconium is the source of the closest mimic of diamond - Cubic Zirconia (CZ). It is popularly fashioned as a diamond simulant (non-diamond material).

# Given the metal's low absorption of neutrons, and significant resistant towards heat and chemical corrosion, it is widely used in the working of nuclear reactors.

Here the metal is used to provide an outer covering to components such as the fuel rods that run the reactor. As a matter of fact the nuclear power industry exploits 90% of the metal produced each year.

# As the metal is extremely high on the corrosion-resistance factor, it finds its applications in many industries which make use of corrosive agents such as in high-performance pumps, valves, etc.

# Zirconium oxide or zirconia, is mainly used in the manufacture of ceramic materials. It is an inorganic metal oxide, and a compound of zirconium. It is also used as a gemstone as it has a high refractive index.

# The main sources of zirconium are the minerals called zircon (ZrSiO4) and baddeleyite (ZrO2). A process known as the Kroll process is applied to obtain the metal from these minerals.

# Another use of zirconium is evident by black zirconium rings. These rings are available in elegant and luxurious designs for fashion-conscious people. These rings are scratch-resistant and do not sustain the wear and tear unlike other common metals.

# A common ingredient in antiperspirant is aluminum zirconium. It is, however, related to the development of breast cancer and Alzheimer's Disease. But there is no solid evidence to back this fact, and there are many controversies regarding the ill effects of the same.

# Zirconium also finds its application in steel as an alloying agent. Vacuum tubes, different surgical appliances, lamp filaments, piping, artificial joints and limbs require this metal. Apart from these, the metal is employed in photoflash bulbs, explosive primers, rayon spinnerets, etc.

To conclude with one more fact about this useful metal, although discovered in the year 1789, zirconium was isolated in an impure form in 1824 by Jakob Berzelius. And until 1914, the pure form wasn't prepared.