Vanadium liquid

Analytical methods applied to estimate oxygen in alkali metals are the fast neutron activation for lithium oxide in lithium, vacuum distillation of excess alkali metal and analysis of the residue by atomic absorption spectrometry to estimate oxygen in sodium, as well as in the heavier alkali metals. Equilibration of oxygen between getters such as vanadium, liquid alkali metals and solid electrolyte oxygen meters, can be applied in several alkali metals. They measure oxygen activities directly in alkali metal circuits or closed containers. 

Vanadium oxide tribromide, VOBr3. Dark red deliquescent liquid formed by heating V2O3 plus Brj. 

Vanadium IV) chloride, VCI4, b.p. 154 C. Reddish brown liquid formed V plus CI2. Decomposes slowly to VCI3 and CU hydrolysed by water. 

Vanadium oxide trichloride, VOCI3, vanadyl chloride. Readily prepared yellow liquid, b.p. 127 C, formed CK plus heated V2OS plus C. Readily hydrolysed by water. 

Vapor-phase oxidation over a promoted vanadium pentoxide catalyst gives a 90% yield of maleic anhydride [108-31-6] (139). Liquid-phase oxidation with a supported palladium catalyst gives 55% of succinic acid [110-15-6] (140). 

Liquid-Phase Epoxidation with Hydroperoxides. Molybdenum, vanadium, and tungsten have been proposed as Hquid-phase catalysts for the oxidation of the ethylene by hydroperoxides to ethylene oxide (205). tert- uty hydroperoxide is the preferred oxidant. The process is similar to the arsenic-catalyzed route, and iacludes the use of organometaUic complexes. 

The production of metals which form very stable oxides by tire aluminothermic process, such as manganese, clrromium and vanadium is carried out with reactants at room temperature which react to provide enough heat to raise the temperature of the products to high temperatures at which the whole system is liquid. The metal phase which is produced can therefore separate from the liquid slag which is formed. The production of clrromium serves as a useful... 

Liquid fuels require atomization and treatment to inhibit sodium and vanadium content. Liquid fuels can drastically reduce the life of a unit if not properly treated. A typical fuel system is shown in Figure 4-7. The effect of fuels on gas turbines and the details of types of fuel handling systems is given in Chapter 12. 

Hot corrosion is a rapid form of attack that is generally associated with alkali metal contaminants, such as sodium and potassium, reacting with sulfur in the fuel to form molten sulfates. The presence of only a few parts per million (ppm) of such contaminants in the fuel, or equivalent in the air, is sufficient to cause this corrosion. Sodium can be introduced in a number of ways, such as salt water in liquid fuel, through the turbine air inlet at sites near salt water or other contaminated areas, or as contaminants in water/steam injections. Besides the alkali metals such as sodium and potassium, other chemical elements can influence or cause corrosion on bucketing. Notable in this connection are vanadium, primarily found in crude and residual oils. 

Sodium and potassium are restricted because they react with sulfur at elevated temperatures to corrode metals by hot corrosion or sulfurization. The hot-corrision mechanism is not fully understood however, it can be discussed in general terms. It is believed that the deposition of alkali sulfates (Na2S04) on the blade reduces the protective oxide layer. Corrosion results from the continual forming and removing of the oxide layer. Also, oxidation of the blades occurs when liquid vanadium is deposited on the blade. Fortunately, lead is not encountered very often. Its presence is primarily from contamination by leaded fuel or as a result of some refinery practice. Presently, there is no fuel treatment to counteract the presence of lead. 

Cyclohexenone has been prepared by dehydrohalogenation of 2-bromocyclohexanone, by the hydrolysis and oxidation of 3-chlorocyclohexene, by the dehydration of a-hydroxycyclohexa- ione, by the oxidation of cyclohexene with chromic acid or hydrogen peroxide in the presence of a vanadium catalyst, by I lie addition of acroleiti to ethyl acetoacctate followed by cycliza-lion, hydroly.sis, and decar])oxylation, by the reduction of N,N-dimelliyliiniline with sodium and ethanol itt liquid ammonia... 

The nitric acid is warmed gently on the water-bath in a larj O flask (I litre) with the addition of the vanadium pentoxidc. It then placed in the fume cupboard and the cane sugar at onc f added.. As soon as torrents of brown fumes begin to be evolved, the flask is placed in cold water. After the reaction has ceased tin liquid is left for twenty-four hours when colourless crystals of the acid separate. A further small quantity may be obtained fiom the mother liquor on standing. The ciystals are drained oia a small porcelain funnel without filter paper, and recrystallised from a very small quantity of water. Yield, 15—20 grams. 

Figure 4.1-1 Liquid sample cells made from (a) TiZr alloy and (b) vanadium.

Scheme 6.1-2 Vanadium oxo-exchange chemistry in a basic [EMIM]CI/AICl3 ionic liquid...

Loop Tests Loop test installations vary widely in size and complexity, but they may be divided into two major categories (c) thermal-convection loops and (b) forced-convection loops. In both types, the liquid medium flows through a continuous loop or harp mounted vertically, one leg being heated whilst the other is cooled to maintain a constant temperature across the system. In the former type, flow is induced by thermal convection, and the flow rate is dependent on the relative heights of the heated and cooled sections, on the temperature gradient and on the physical properties of the liquid. The principle of the thermal convective loop is illustrated in Fig. 19.26. This method was used by De Van and Sessions to study mass transfer of niobium-based alloys in flowing lithium, and by De Van and Jansen to determine the transport rates of nitrogen and carbon between vanadium alloys and stainless steels in liquid sodium. 

Liquid Iron Titanium Molybdenum Vanadium Uranium Tungsten... 

Reductant equivalent weights of, 847 Reduction 409 by chromium(II) salts, 409 by hydrogen sulphide, 416 by Jones reductor (zinc amalgam), 410 by liquid amalgams, 412 by silver reductor, 414 by sulphurous acid, 416 by tin(II) chloride, 415 by titanium(II[), 410 by vanadium(II), 410 see also Iron(III), reduction of Reduction potentials 66 Reference electrodes potentials, (T) 554 Relative atomic masses (T) 819 Relative error 134 mean deviation, 134... 

The commercial production of stabilized liquid sulfur trioxide and the assessment of its advantages led to increased use [47-49]. Later development of specialized sulfur burners with catalytic conversion of sulfur dioxide to sulfur trioxide in air by vanadium pentoxide has established this method as an alternative to liquid sulfur trioxide. 

Electronic Grade Silicon (EGS). As the first step in the production of electronic grade silicon (EGS), an impure grade of silicon is pulverized and reacted with anhydrous hydrochloric acid, to yield primarily tricholorosilane, HSiClg. This reaction is carried out in afluidizedbed at approximately 300°C in the presence of a catalyst. At the same time, the impurities in the starter impure silicon reactto form their respective chlorides. These chlorides are liquid at room temperature with the exception of vanadium dichloride and iron dichloride, which are soluble in HSiCl3 at the low concentration prevailing. Purification is accomplished by fractional distillation. 

Liquid chlorine in contact with powdered vanadium causes the mixture to detonate. 

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