The currently known processes for extracting titanium from its various ores are laborious and costly; it is not possible to reduce the ore by heating with carbon (as in iron smelting) because titanium combines with the carbon to produce titanium carbide. [51] Pure metallic titanium (99.9%) was first prepared in 1910 by Matthew A. Hunter at Rensselaer Polytechnic Institute by heating TiCl 4 with sodium at 700–800°C (1,292–1,472°F) under great pressure [57] in a batch process known as the Hunter process. [8] Titanium metal was not used outside the laboratory until 1932 when William Justin Kroll produced it by reducing titanium tetrachloride (TiCl 4) with calcium. [58] Eight years later he refined this process with magnesium and with sodium in what became known as the Kroll process. [58] Although research continues to seek cheaper and more efficient routes, such as the FFC Cambridge process, the Kroll process is still predominantly used for commercial production. [8] [9] Titanium "sponge", made by the Kroll process Around the same time, Franz-Joseph Müller von Reichenstein produced a similar substance, but could not identify it. [9] The oxide was independently rediscovered in 1795 by Prussian chemist Martin Heinrich Klaproth in rutile from Boinik (the German name of Bajmócska), a village in Hungary (now Bojničky in Slovakia). [51] [a] Following the success of platinum-based chemotherapy, titanium(IV) complexes were among the first non-platinum compounds to be tested for cancer treatment. The advantage of titanium compounds lies in their high efficacy and low toxicity in vivo. [50] In biological environments, hydrolysis leads to the safe and inert titanium dioxide. Despite these advantages the first candidate compounds failed clinical trials due to insufficient efficacy to toxicity ratios and formulation complications. [50] Further development resulted in the creation of potentially effective, selective, and stable titanium-based drugs. [50] History Martin Heinrich Klaproth named titanium for the Titans of Greek mythology. The most important oxide is TiO 2, which exists in three important polymorphs; anatase, brookite, and rutile. All three are white diamagnetic solids, although mineral samples can appear dark (see rutile). They adopt polymeric structures in which Ti is surrounded by six oxide ligands that link to other Ti centers. [33]

A brief tutorial in Titanium Ion Plating - John Desmond Ltd. A brief tutorial in Titanium Ion Plating - John Desmond Ltd.

The +4 oxidation state dominates titanium chemistry, [29] but compounds in the +3 oxidation state are also numerous. [30] Commonly, titanium adopts an octahedral coordination geometry in its complexes, [31] [32] but tetrahedral TiCl 4 is a notable exception. Because of its high oxidation state, titanium(IV) compounds exhibit a high degree of covalent bonding. [29] Oxides, sulfides, and alkoxidesBecause it cannot be readily produced by reduction of titanium dioxide, [14] titanium metal is obtained by reduction of TiCl 4 with magnesium metal in the Kroll process. The complexity of this batch production in the Kroll process explains the relatively high market value of titanium, [65] despite the Kroll process being less expensive than the Hunter process. [57] To produce the TiCl 4 required by the Kroll process, the dioxide is subjected to carbothermic reduction in the presence of chlorine. In this process, the chlorine gas is passed over a red-hot mixture of rutile or ilmenite in the presence of carbon. Titanium tetrachloride (titanium(IV) chloride, TiCl 4 [44]) is a colorless volatile liquid (commercial samples are yellowish) that, in air, hydrolyzes with spectacular emission of white clouds. Via the Kroll process, TiCl 4 is used in the conversion of titanium ores to titanium metal. Titanium tetrachloride is also used to make titanium dioxide, e.g., for use in white paint. [45] It is widely used in organic chemistry as a Lewis acid, for example in the Mukaiyama aldol condensation. [46] In the van Arkel–de Boer process, titanium tetraiodide (TiI 4) is generated in the production of high purity titanium metal. [47]

Titanium | Element, Meaning, Symbol, Density, Properties

Titanium readily reacts with oxygen at 1,200°C (2,190°F) in air, and at 610°C (1,130°F) in pure oxygen, forming titanium dioxide. [12] Titanium is one of the few elements that burns in pure nitrogen gas, reacting at 800°C (1,470°F) to form titanium nitride, which causes embrittlement. [22] Because of its high reactivity with oxygen, nitrogen, and many other gases, titanium that is evaporated from filaments is the basis for titanium sublimation pumps, in which titanium serves as a scavenger for these gases by chemically binding to them. Such pumps inexpensively produce extremely low pressures in ultra-high vacuum systems. Common titanium-containing minerals are anatase, brookite, ilmenite, perovskite, rutile, and titanite (sphene). [20] Akaogiite is an extremely rare mineral consisting of titanium dioxide. Of these minerals, only rutile and ilmenite have economic importance, yet even they are difficult to find in high concentrations. About 6.0 and 0.7 million tonnes of those minerals were mined in 2011, respectively. [24] Significant titanium-bearing ilmenite deposits exist in Australia, Canada, China, India, Mozambique, New Zealand, Norway, Sierra Leone, South Africa, and Ukraine. [20] About 210,000 tonnes of titanium metal sponge were produced in 2020, mostly in China (110,000 t), Japan (50,000 t), Russia (33,000 t) and Kazakhstan (15,000 t). Total reserves of anatase, ilmenite, and rutile are estimated to exceed 2 billion tonnes. [24] 2017 production of titanium minerals and slag [24] Country The alkoxides of titanium(IV), prepared by treating TiCl 4 with alcohols, are colorless compounds that convert to the dioxide on reaction with water. They are industrially useful for depositing solid TiO 2 via the sol-gel process. Titanium isopropoxide is used in the synthesis of chiral organic compounds via the Sharpless epoxidation. [37]FeTiO 3 + 7 Cl 2 + 6 C → 900 o C 2 FeCl 3 + 2 TiCl 4 + 6 CO {\displaystyle {\ce {2FeTiO3 + 7Cl2 + 6C ->[900 Titanium nitride (TiN) is a refractory solid exhibiting extreme hardness, thermal/electrical conductivity, and a high melting point. [39] TiN has a hardness equivalent to sapphire and carborundum (9.0 on the Mohs scale), [40] and is often used to coat cutting tools, such as drill bits. [41] It is also used as a gold-colored decorative finish and as a barrier layer in semiconductor fabrication. [42] Titanium carbide (TiC), which is also very hard, is found in cutting tools and coatings. [43] Halides Titanium(III) compounds are characteristically violet, illustrated by this aqueous solution of titanium trichloride. Titanium is not as hard as some grades of heat-treated steel; it is non-magnetic and a poor conductor of heat and electricity. Machining requires precautions, because the material can gall unless sharp tools and proper cooling methods are used. Like steel structures, those made from titanium have a fatigue limit that guarantees longevity in some applications. [14] The two most useful properties of the metal are corrosion resistance and strength-to-density ratio, the highest of any metallic element. [10] In its unalloyed condition, titanium is as strong as some steels, but less dense. [11] There are two allotropic forms [12] and five naturally occurring isotopes of this element, 46Ti through 50Ti, with 48Ti being the most abundant (73.8%). [13] Characteristics Physical properties

Titanium - Element information, properties and uses

See also: van Arkel–de Boer process Titanium (mineral concentrate) Basic titanium products: plate, tube, rods, and powder The term titanates usually refers to titanium(IV) compounds, as represented by barium titanate (BaTiO 3). With a perovskite structure, this material exhibits piezoelectric properties and is used as a transducer in the interconversion of sound and electricity. [12] Many minerals are titanates, such as ilmenite (FeTiO 3). Star sapphires and rubies get their asterism (star-forming shine) from the presence of titanium dioxide impurities. [20]Owing to the important role of titanium compounds as polymerization catalyst, compounds with Ti-C bonds have been intensively studied. The most common organotitanium complex is titanocene dichloride ((C 5H 5) 2TiCl 2). Related compounds include Tebbe's reagent and Petasis reagent. Titanium forms carbonyl complexes, e.g. (C 5H 5) 2Ti(CO) 2. [49] Anticancer therapy studies Klaproth found that it contained a new element and named it for the Titans of Greek mythology. [26] After hearing about Gregor's earlier discovery, he obtained a sample of manaccanite and confirmed that it contained titanium. [56] Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine. The processing of titanium metal occurs in four major steps: reduction of titanium ore into "sponge", a porous form; melting of sponge, or sponge plus a master alloy to form an ingot; primary fabrication, where an ingot is converted into general mill products such as billet, bar, plate, sheet, strip, and tube; and secondary fabrication of finished shapes from mill products. [64] metal displacement reactions e.g. the less reactive titanium is displaced by the more reactive sodium or magnesium.