Titanium oxide melting point

Stable oxides, such as those of clrromium, vanadium and titanium cannot be reduced to the metal by carbon and tire production of these metals, which have melting points above 2000 K, would lead to a refractoty solid containing carbon. The co-reduction of the oxides widr iron oxide leads to the formation of lower melting products, the feno-alloys, and tlris process is successfully used in industrial production. Since these metals form such stable oxides and carbides, tire process based on carbon reduction in a blast furnace would appear to be unsatisfactory, unless a product samrated with carbon is acceptable. This could not be decarburized by oxygen blowing without significairt re-oxidation of the refractory metal. 

There are two important titanium aluminides Tig A1 which has a hexagonal structure with a density of 4.20 g/cm and a melting point of 1600°C and Ti A1 which has a tetragonal structure with a density of 3.91 g/cm and a melting point of 1445°C. As do all aluminides, they have excellent high temperature oxidation resistance owing to the formation of a thin alumina layer on the surface. They have potential applications in aerospace structures. 

For example, titanium is a non-volatile metal with a melting point of about 1660 °C and boiling point approaching 3320 °C. The oxide Ti02 has melting and boiling points of 1870 and 3827 °C, respectively. In the... 

Halides of metals tend to be ionic unless the metal has an oxidation number greater than +2. For example, sodium chloride and copper(ll) chloride are ionic compounds with high melting points, whereas titanium(lV) chloride and iron(lll) chloride sublime as molecules. 

The V-Ti-0 system has been extensively studied in connection with catalytic oxidation and ammoxidation reactions of aromatic hydrocarbons. Two principally different types of catalysts can be distinguished. One type of catalyst is prepared by impregnation, precipitation or mixing of the vanadium and titanium phases followed by calcination in air below the melting point of V. (1-4). The simultaneous reduction of V 0- and transformation of iiO (anatase) into rutile when heating below the V O melting point has been demonstrated to be due to topotactic reactions ( ). The formation of lower vanadium oxides can be of importance, because it has been found that reduced phases determine the activity and selectivity of catalysts (6,7). 

Zirconium (Zr, CAS 7440-67-7, atomic number 40, atomic mass 91.22) has a melting point of 1852 °C and a boiling point of 4377 °C. It is a hard, lustrous, silvery metal, in contrast to fine zirconium powder, which is black. Zirconium belongs to Subgroup IV of the Periodic Table of the elements, between the elements titanium and hafnium - two metals with which it is often found in nature. Zirconium has oxidation states ranging from II to IV, of which the tetravalent is relatively stable and abundant (Venugopal and Luckey 1979). Zirconium is very corrosion-resistant and is unaffected by alkalis or acids (except for HF). 

---