Sodium-vanadium oxide compounds

High 50,000 0,000 8-16 Aluminum, copper, zinc, vanadium, calcined dolomite, hme, magnesia, magnesium carhonates, sodium chloride, sodium and potassium compounds Flue dust, natural and reduced iron ores Flue dust, iron oxide, natural and reduced iron ores, scrap metals... 

High (e.g. 50-80 X 103 lb/in.2) 8-16 Metal powders (zinc, vanadium etc.), calcined dolomite, lime, magnesia, magnesium carbonate, sodium and potash compounds, hay and straw Fly-ash, raw and reduced iron ores Fly-ash, iron oxides, raw and reduced iron ores, scrap... 

Vanadium ores are heated to high temperatures with sodium chloride in air to obtain water-soluble sodium vanadate, which is then leached with dilute acids so that a vanadium oxide can be obtained. The precipitate is dissolved in a sodium carbonate solution and ammonium chloride is added to precipitate NH4VO3. Intense heating of NH4VO3 causes it to decompose to V2O5, which is the commercial vanadium compound [13]. Vanadium metal can be purified by several methods including iodine refining [13]. 

In contrast to the above discussion, vanadium oxide is also known to play a crucial role in the deactivation of ultra stable Y (USY) zeolite in fluid cata-lylic cracking (FCC) processes. Vanadium is known to enhance the removal of sodium ions from zeolite Y, thereby acting as a promoter/catalyst. These Na+ ions released are known to attack and destroy the Si-OSi frame in the zeolite there by deactivating it. The source of vanadium in FCC processes comes from crude oil (feed) which contain V-porphyrin and organo-vanadium compounds. The released vanadium migrates to the surface of zeolite. In this process, vanadium is known to fluctuate between oxidation states there by making it a redox... 

The degree of slagging, is, in turn, closely related to the concentration of vanadium, nickel, and sodium compounds present in the fuel, and the types of low melting-point oxides and complex sticky deposits formed under specific boiler temperatures and prevailing conditions. These deposits are difficult to remove online with soot blowers, but... 

All classes of primary amine (including primary, secondary, and tertiary alkyl as well as aryl) are oxidized to nitro compounds in high yields with dimethyl dioxirane." Other reagents that oxidize various types of primary amines to nitro compounds are dry ozone, various peroxyacids," MeRe03/H202,"" Oxone ," ° tcrt-butyl hydroperoxide in the presence of certain molybdenum and vanadium compounds, and sodium perborate." ... 

The effect of inorganic additives upon ignition delay in anilinium nitrate-red finning nitric acid systems was examined. The insoluble compounds copper(I) chloride, potassium permanganate, sodium pentacyanonitrosylferrate and vanadium(V) oxide were moderately effective promoters, while the soluble ammonium or sodium metavanadates were very effective, producing vigorous ignition. 

Merox [Mercaptan oxidation] A process for removing mercaptans from petroleum fractions by extracting them into aqueous sodium hydroxide and then catalytically oxidizing them to disulfides using air. The catalyst is an organometallic compound, either a vanadium phthalocyanine supported on charcoal, or a sulfonated cobalt phthalocyanine. Developed by UOP in 1958 and widely licensed by 1994, more than 1,500 units had been built, worldwide. Unzelman, G. H. and Wolf, C. J., in Petroleum Processing Handbook, Bland, W. F. and Davidson, R. L., Eds., McGraw-Hill, New York, 1967, 3-128. 

Vanadium and sodium compounds present in the fuel are oxidized during fuel combustion to V205 and Na20. 

Compounds of Vanadium in Lower Oxidation States. Melt paraffin in a porcelain bowl or test tube. Put seven test tubes with stoppers onto a test tube stand. Pour 10 ml of a sodium vanadate solution into a small 50-ml flask, add 10 ml of a 20% sulphuric acid solution, and put in 8-10 small pieces of granulated zinc. Watch how the solution s colour changes. As a new colour appears, pour off 1-2 ml of the solution into each of three of the tubes. In one of them, pour melted paraffin over each layer of liquid with a new colour. Close the other two tubes with their stoppers and pour the following portion of the solution with a new colour into two empty tubes with stoppers. 

Rapidly add a 10% sodium hydroxide solution to one series of solutions containing compounds of vanadium in different oxidation states. What do you observe See how the obtained hydroxides react with acids and alkalies. Add a potassium permanganate solutioq... 

In some cases, however, the modus operandi is modified. In the oxidation of hydriodic acid with chromic acid, the data indicate that while liberation of iodine takes place, the vanadous or hypovanadic salt employed as the catalyst also undergoes oxidation to vanadate.2 The vanadium compound here belongs to the class of catalysts known as inductors, and the reaction is comparable to the oxidation in aqueous solution of sodium sulphite with sodium arsenite, whereby both sodium sulphate and sodium arsenate are produced. 

Detection.—Apart from naturally occurring ores of vanadium, vanadium steels, and ferrovanadium, the commonest compounds of vanadium are those which contain the element in the pentavalent state, viz. the pentoxide and the various vanadates. The analytical reactions usually employed are, therefore, those which apply to vanadates. Most vanadium ores can be prepared for the application of these reactions by digesting with mineral acids or by alkaline fusion with the addition of an oxidising agent. When the silica content is high, preliminary treatment with hydrofluoric acid is recommended. Vanadium steels and bronzes, and ferrovanadium, are decomposed by the methods used for other steels the drillings are, for instance, dissolved in sulphuric acid and any insoluble carbides then taken up in nitric acid, or they are filtered off and submitted to an alkaline fusion. Compounds of lower valency are readily converted into vanadates by oxidation with bromine water, sodium peroxide, or potassium permanganate. 

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