Ilmenite, FeTiO

Titanium, Ti, atomic number 22, relative atomic mass 47.90, is the ninth most common element (ca 0.6% by weight) and is widely distributed in the earth s cmst. It is found particularly in the ores mtile, Ti02, and ilmenite, FeTiO. ... 

Titanium, Ti, a light, strong metal, is used where these properties are critical— in widely diverse applications such as jet engines and dental fixtures such as partial plates. Although titanium is relatively reactive, unlike scandium it is resistant to corrosion because it is passivated by a protective skin of oxide on its surface. The principal sources of the metal are the ores ilmenite, FeTiO , and rutile, Ti02. 

Titanium occurs in nature in the minerals rutile( Ti02), ilmenite (FeTiOs), geikielite, (MgTiOs) perovskite (CaTiOs) and titanite or sphene (CaTiSi04(0,0H,F)). It also is found in many iron ores. Abundance of titanium in the earth s crust is 0.565%. Titanium has been detected in moon rocks and meteorites. Titanium oxide has been detected in the spectra of M-type stars and interstellar space. 

Titanium is mined as rutile (Ti02) and ilmenite (FeTiOs). The refined oxide is an important constituent of paints, while the relatively light but highly corrosion-resistant metal is increasingly used structurally and for chemical process equipment despite its high cost. 

Titanium was discovered in 1791 by an English clergyman and amateur chemist, William Gregor. He identified it in a black sand (now known to be ilmenite, FeTiOs, named after Russia s Ilmen lake and mountains) from the Menacchan Valley in Cornwall Four years later, the German chemist M. H. Klaproth independently discovered the element in the Ti02... 

Brown, N.E., Navrotsky, A., Nord, G.L., Baneijee, S.K. (1993) Hematite (Fe203)-ilmenite (FeTiOs) solid solutions Determinations of FeTi order from magnetic properties. Am Mineral 78 941-951 Burton, B.P. (1987) Theoretical analysis of cation ordering in binary rhombohedral carbonate systems. Am Mineral 72 329-336... 

The two most important minerals of titanium are ilmenite (FeTiOs) and rutile (Ti02). The former is a black sandy material mined in Canada, the USA, Australia, Scandinavia and Malaysia, while the latter is mined principally in Australia. Zirconium s main minerals are zircon (ZrSi04)... 

When M° is approximately the same size as Ti (i.e. M = Mg, Mn, Fe, Co, Ni) the structure is that of ilmenite, FeTiOs, which consists of hep oxygens with one-third of the octahedral interstices occupied by and another third by Ti This is essentially the same structure as corundum (AI2O3, p. 243) except that in that case there is only one type of cation which occupies two-thirds of the octahedral sites. 

U.S. production in these years was around 150,000 short tons. Thus, Australia and the United States are the principal zirconium-producing nations. Most of their production was from dredging of black sands on beaches and in stream beds, where zircon has been concentrated hydraulically along with other relatively dense minerals such as rutile (TiOj), ilmenite (FeTiOs), and monazite (Chap. 6). 

Conventional (SulfiM ) Process. Raw material is either an ilmenite (FeTiO ) concentrate from benefidation of naturally occurring ilmenite or a slag obtained from ilmenite by electrosmelting and tapping off the major part of the iron as pig iron for further use. The titaniferous material is digested with concentrated sulfuric acid, leading to a solution of sulfates of most of the metals contained in the ore, e.g. ... 

Titania is also produced by reacting ilmenite FeTiOs with sulfuric acid at 150-180°C to form titanyl sulfate, TiOS04 ... 

Table 31.7 lists some other ferroelectric ceramics, although it does not include the large number of solid-solution phases that are ferroelectric. Many ferroelectric ceramics have a perovskite structure above 0c, but this is not a prerequisite. For example, LiNbOs has an ilmenite (FeTiOs) structure and Cd2Nb207 has a pyrochlore structure (the mineral pyrochlore is CaNaNb20eF). 

Mendeleev continued how especially important it was for him to obtain as large an amount of titanium minerals as possible, together with their place of origin, if possible. Specifically rutile [TiOJ, ilmenite [FeTiOs], and also other minerals zirconium [Zr], orthite, or cerite and eschynite. Dmitrii Ivanovich quickly... 

As expected, catalysts without potassium deactivate rapidly during dehydrogenation, since no compounds capable of gasifying carbonaceous deposits are present in these systems (Fig. 3) [3,11]. However, the deactivation of iron-on-titania proceeds relatively more rapidly. This is attributed to the formation of inactive ilmenite (FeTiO,) in this ca yst under reaction conditions [17]. When potassium is added to avoid deactivation (Fig. 4), it can be seen that deactivation is effectively suppressed in the system supported on zirconia, but that the system... 

Pure primary titanium dioxide does not occur naturally, but is derived by weathering from ilmenite (FeTiOs), perovskite (CaTiOs), and titanite (sphene) (CaTiSiO ). The weathering products form leuxocene ores with up to 68% mtile content. The... 

Similarly, intrinsic ionization may also take place by charge transfer. In ilmenite, FeTiOs, we may for instance observe the reaction + Ti = Fe " + which in terms of defects is written ... 

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