Titanium

Titanium is a chemical element with symbol Ti and atomic number 22. It is a lustrous transition metal with a silver colour, low density, and high strength.

History and Discovery

Titanium was discovered by William Gregor in 1791 (Great Britain) [1]. Pure titanium was obtained after a long struggle of 119 years, by Matthew Hunter in 1910.Titanium was used for the first time in making military applications by Soviet Union in 1950s. And later, US defense department recognized the significance of titanium and set motion to commercialization of titanium-based war strategic material.  The element was name Titanium after the Greek Gods, Titans by Martin Klaproth.

Titanium

Periodic Table ClassificationGroup 4
Period 4
State at 20CSolid
ColorSilvery grey-white metallic
Electron Configuration[Ar] 3d2 4s2
Electron Number22
Proton Number22
Electron Shell2, 8, 10, 2
Density4.54 g.cm-3 at 20°C
Atomic number22
Atomic Mass47.87 g.mol -1
Electronegativity according to Pauling1.54

Occurrence

Titanium is an abundant element and is characterized as the 9th most abundant element in the Earth’s crust [2]. Native or elemental titanium is very rare. It exists in form of compounds in minerals. Mostly, it is present as oxides in igneous rocks and sediments. The common minerals of titanium include brookite, sphene (calcium titanium silicate), perovskite, titanite, anatase and rutile (titanium oxide). The minerals of economic importance are ilmenite (iron titanium oxide) and rutile, and around 0.7 million tons were mined in 2011Titanium is also present in ocean water with a concentration of around 4 picomoles [3]. Titanium is present in extraterrestrial environment, including the sun, moon, meteorites and certain type of stars. The main producers of titanium include India, US, New Zealand, China, Canada, South Africa and Norway.

Physical Characteristics

Titanium is a silvery white lustrous metal. it is quite light-weight as compared to other metals. it has an outstanding strength and durability. Titanium is highly resistant to corrosion. The rate of corrosion of titanium is so slow that it will be barely rusted after 4000 years of sea water exposure. When heated, titanium is ductile and malleable. Titanium is insoluble in water. however, it is readily dissolved in concentrated sulfuric and nitric acids.

Chemical Characteristics

Titanium exists in two oxidations states, +4 and +3. The most common oxidation state of titanium in compounds is +4 [4]. the titanium (IV) compounds are usually termed as titanates.  Titanium frequently forms covalent bonds with its compounds. Titanium form titanium oxides with oxygen, and there are three forms of titanium oxide, rutile, anatase and brookite. Titanium forms compound with sulfur.

Significance and Uses

  • Titanium is widely used in making esteem quality steel alloys. It is also used in making of other alloys such as, copper, vanadium and aluminum.
  • Titanium products are widely used in various aerospace, and industrial markets.
  • Titanium in the form of titanium dioxide is used in the making of white colored plastic products, toothpaste, paints, and paper.
  • Titanium is widely used as a strengthening material in the making of fishing rods, helmets, hockey, tennis racket, drill bits etc.
  • Titanium is widely used in automotive applications, such as bikes, sports car and automobile, as it is light weight and has high strength.
  • Titanium is used in making structure of ships, shafts etc. as it is extraordinarily resistant to corrosion by sea water.
  • Titanium is used in making of prosthetic joints for joint replacement therapy , such as hip joint and also as dental implants.
  • Titanium is used in making various electronics including high end cameras, mobiles, and laptops.
  • Nanoparticles of titanium are used as delivery tool for various drugs.

Health Hazards

Titanium is a low toxic metal. However, certain compounds including titanium chlorides are quite corrosive.  In powder from, titanium is readily combustible.

Isotopes of Titanium

There are eighteen isotopes of titanium. There are five stable isotopes present in naturally occurring titanium: titanium-46, titanium-47, titanium-48, titanium-49, and titanium-50.  The most abundant natural isotope is titanium-48 (73.8%). There are also eleven radioactive isotopes of titanium and among them titanium-44 is the most stable. The radioactive isotopes of titanium emit gamma rays and positrons.

REFERENCES

[1]. William Gregor, Beobachtungen und Versuche über den Menakanite, einen in Cornwall gefundenen magnetischen Sand., in Lorenz Crell’s Chemische Annalen, 1791, p40

[2]. Barksdale 1968, p. 732

[3]. “Titanium”. Encyclopædia Britannica. 2006. Retrieved 29 December 2006.

[4]. Greenwood 1997, p. 970