Titanium oxide boiling point

Table 3 (3) shows the influence of branching of the alkyl group on volatility and complexity, usiag titanium and zirconium amyl oxides as examples. Table 3. Boiling Points and Molecular Complexities of Amyloxides of Titanium and of Zirconium...

The volatile chlorides ate collected and the unreactedsohds and nonvolatile chlorides ate discarded. Titanium tetrachloride is separated from the other chlorides by double distillation (12). Vanadium oxychloride, VOCl, which has a boiling point close to TiCl, is separated by complexing with mineral oil, reducing with H2S to VOCI2, or complexing with copper. The TiCl is finally oxidized at 985°C to Ti02 and the chlorine gas is recycled (8,11) (see also... 

The solvent process involves treating phthalonitrile with any one of a number of copper salts in the presence of a solvent at 120 to 220°C [10]. Copper(I)chloride is most important. The list of suitable solvents is headed by those with a boiling point above 180°C, such as trichlorobenzene, nitrobenzene, naphthalene, and kerosene. A metallic catalyst such as molybdenum oxide or ammonium molybdate may be added to enhance the yield, to shorten the reaction time, and to reduce the necessary temperature. Other suitable catalysts are carbonyl compounds of molybdenum, titanium, or iron. The process may be accelerated by adding ammonia, urea, or tertiary organic bases such as pyridine or quinoline. As a result of improved temperature maintenance and better reaction control, the solvent method affords yields of 95% and more, even on a commercial scale. There is a certain disadvantage to the fact that the solvent reaction requires considerably more time than dry methods. 

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... 

Metal salts may be used in the treatment of wool. Flame methods for the determination of aluminium [185], barium, chromium, copper, mercury, strontium, tin, zinc [186] and zirconium [187] in wool have been published. Standard additions to wool cleaned by soaking and washing it with disodium EDTA (800 ml of 0.5 M for 30g wool with soaking for 3 days and double washing) was used as the calibration technique. This compensated for interferences from hydrochloric acid and amino-acids. The samples were equilibrated to a constant humidity for 24 h and then 0.3 g sealed with 5 ml of constant boiling point hydrochloric acid in a glass tube. The tubes were placed in an oven at 110UC for 20 h. The nitrous oxide/acetylene flame was used for the determination of aluminium and zirconium. Sulphate, phosphate, citrate and silicate have been found to interfere in the determination of titanium and zirconium in fire-proofed wool [188], These flame... 

Besides alkoxides, acetylacetonates are also used as the starting materials for the synthesis of oxides. Titania (anatase) is obtained by decomposition of titanium oxyacetylacetonate (TiO(acac)2) in toluene at 300°C. Similarly solvothermal treatment of Fe(lll) acetylacetonate in toluene yields microcrystalline magnetite. One of the drawbacks of the use of acetylacetonate may be formation of various high boiling point organic by-products via aldol-type condensation of the acetylacetone. Actually more than 50 compounds are detected by gas chromatography-mass spectrometry (GC-MS) analysis of the supernatant of the reaction, some of which are phenolic compounds and are hardly removed from the oxide particles by washing with acetone. ... 

Notice that each value of AG° refers to one mole of 02 or Cl2 as appropriate. Notice also that were it not for the reducing effect of the carbon, the reaction would not be possible. (There are several metal oxides, for example those of copper, iron and zinc, which may be chlorinated by chlorine alone.) The TiCl4 is a volatile, essentially covalent liquid with a boiling point of 136°C, which must be of high purity if a high quality titanium product is to be obtained. 

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). 

The reactions of metals to form stable halides are important for various reasons. The metal halides generally have low boiling points and high volatiUty. For this reason, they are used in several important processes for the production and refining of metals, such as the reactive metals titanium and zirconium. These metals are produced using the Kroll process, in which the metal oxide is converted to metal chloride or fluoride, which is then reduced to metal. This route avoids several formidable difficulties involved in the reduction of the oxides of these metals. Details of these processes can be found in extractive-metallurgy textbooks. 

Titanium(IV) bromide may be prepared by passing bromine vapor over a heated mixture of titanium(IV) oxide and carbon or by the action of hydrogen bromide on titanium(IV) chloride heated just below its boiling point. The following directions are for the former method. 

Metallic chromium is also produced by an electrolytic method. Ferrochromium is crushed and dissolved at a temperature near the boiling point in a mixture of sulfuric acid and used anolyte. In a crystallizer the iron is separated as iron ammonium sulfate at a temperature of 5°C. The temperature in the electrolytic cells is 53°C. In the process sulfuric add and hexavalent chromium are formed in the anolyte. Because of that it must be prevented from mixing with the catholyte. Otherwise the divalent chromium there wiU be oxidized and the chromium predpitation disturbed. The cathode material is 316-type molybdenum-alloyed stainless steel, the anode material silver-alloyed lead or titanium covered with iridium. For environmental reasons dichromate plants are dosed and the aluminothermic part of the chromium metal production increases. About 1990 it was 60 % and in the begiiming of the 2000s 90 %. 

Tantalum and niobium are, like zirconium and titanium, reactive metals, that is, they rely on an oxide film for corrosion protection. The corrosion behavior of tantalum is similar to that of glass, that is, it can withstand most acids, but not hydrofluoric acid and caustic solutions. Tantalum is inert to nitric acid at all concentrations up to the boiling point and is resistant to hydrochloric acid at all concentrations up to 190 °C (Schussler and Pokross, 1987). There is only one commercially important tantalum alloy (Ta-2.5% W-0.15% Nb) which has corrosion resistance equivalent to that of tantalum (Hunkeler, 1997). When tantalum is coupled with other metals in any industrial application tantalum would generally become cathodic. When exposed to nascent hydrogen tantalum readily absorbs hydrogen and it is very sensitive to hydrogen embrittlement (HE) (Dillon, 1994). The corrosion behavior of niobium is similar to that... 

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