Introduction Of Titanium dioxide

The IUPAC name of Titanium dioxide is Dioxotitanium. With the CAS registry number 13463-67-7, it is also named as Pigment white 6. It belongs to the product categories of Inorganics; Indoles; Inorganic Chemicals. This chemical is white to almost white powder. Its molecular formula is TiO2 and molecular weight is 79.87.
Titanium dioxide occurs in nature as well-known minerals rutile, anatase and brookite, and additionally as two high pressure forms, a monoclinic baddeleyite-like form and an orthorhombic α-PbO2-like form, both found recently at the Ries crater in Bavaria. The most common form is rutile, which is also the equilibrium phase at all temperatures. The metastable anatase and brookite phases both convert to rutile upon heating. Rutile, anatase and brookite all contain six coordinated titanium.
Crude titanium dioxide is purified via converting to titanium tetrachloride in the chloride process. In this process, the crude ore (containing at least 70% TiO2) is reduced with carbon, oxidized with chlorine to give titanium tetrachloride; i.e., carbothermal chlorination. This titanium tetrachloride is distilled, and re-oxidized in a pure oxygen flame or plasma at 1500–2000 K to give pure titanium dioxide while also regenerating chlorine. Aluminium chloride is often added to the process as a rutile promotor; the product is mostly anatase in its absence.
Another widely used process utilizes ilmenite as the titanium dioxide source, which is digested in sulfuric acid. The by-product iron(II) sulfate is crystallized and filtered-off to yield only the titanium salt in the digestion solution, which is processed further to give pure titanium dioxide. Another method for upgrading ilmenite is called the Becher Process. One method for the production of titanium dioxide with relevance to nanotechnology is solvothermal Synthesis of titanium dioxide.

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