Titanium vapor pressure

When the boiling points of metallic impurities are much lower than the boiling point of the main metal, they can simply be distilled away in most cases. The rate and the extent of the removal by distillation of these impurity elements depend upon their partial pressures over the main metal/melt. As an example, let the feasibility of distilling magnesium and magnesium chloride from titanium and calcium from the rare earths be considered. In the firstcase, at 900 °C, the pertinent vapor pressure values are P = 4 10-11 torr, PMg = 105 torr... 

Next, let the example of vanadium, which, in the as-reduced condition, may contain a variety of impurities (including aluminum, calcium, chromium, copper, iron, molybdenum, nickel, lead, titanium, and zinc) be considered. Vanadium melts at 1910 °C, and at this temperature it is considerably less volatile than many of the impurity metals present in it. The vapor pressure of pure vanadium at this temperature is 0.02 torr, whereas those of the impurity elements in their pure states are the following aluminum 22 torr calcium 1 atm, chromium 6 torr copper 23 torr iron 2 torr molybdenum 6 1CT6 torr nickel 1 torr lead 1 torr titanium 0.1 torr and zinc 1 atm. However, since most of these impurities form a dilute solution in vanadium, their actual partial pressures over vanadium are considerably lower than the values indicated. Taking this into account, the vaporization rate, mA, of an element A (the evaporating species) can be approximated by the following free evaporation equation (Langmuir equation) ... 

The vapor pressure of titanium monoxide is much higher than that of zirconium monoxide and hafnium monoxide. However, sacrificial deoxidation is not feasible for titanium because of the relatively high vapor pressure of titanium metal itself. The limiting R value for the titanium-oxygen system is equal to 0.1. 

Titanium (IV) iodide is a lustrous, dark reddish-brown, crystalline solid. It melts at 150°6 and boils at atmospheric pressure without decomposition at 377.2°.3 Its vapor pressure in the range 160 to 370° is given by the relationship ... 

It is evident from the earlier discussion of the titanium-nitrogen system that the final volatilization temperature (3540 K) was controlled by the complete vaporization of the titanium formed due to the dissociation of the product titanium nitride. The partial pressure of titanium vapor was equal to 0.666 atm at the final volatilization temperature of 3540 K (see Fig. 8). Indeed, the vaporization temperature of titanium at 0.666 atm is 3530 K. Consequently, to analyze the results... 

Chemistry and Generation. Titanium tetrachloride (CAS No. 7550-45-0), also known as titanic chloride and has the military code of FM, is a colorless liquid of vapor pressure 10.0 mm Hg (20°C Whitehead, 1983), that fumes strongly when exposed to moist air, forming a persistent dense white cloud (Lewis, 1993). The exothermic reaction products are oxychlorides and hydrogen chloride (Ballantyne, 1982) and finally titanium hydroxide and hydrochloric acid (Lee et al., 1986). One dissemination mode is from aircraft for the production of smoke curtains extending down to ground/sea level (RAMC, 2002). 

Titanium dioxide (CAS 13463-67-7) A mild pulmonary irritant. 10 mg/m 5000 mg/m White odorless powder. Rutile is a common crystalline form. Vapor pressure is negligible. 

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