Uranium pentoxide

Uranium Pentoxide, U2O5.—The existence of this oxide is not definitely established. It has been described as the black product obtained when a uranium salt of a volatile acid is strongly ignited in air when uranyl sulphate, (U02)S04.3H20, is rapidly heated when ammonium diuranate, (NH4)2U207-6H20, is heated in a carbon crucible and when a solution of uranyl nitrate is electrolysed. 

For vanadium solvent extraction, Hon powder can be added to reduce pentavalent vanadium to quadrivalent and trivalent Hon to divalent at a redox potential of —150 mV. The pH is adjusted to 2 by addition of NH, and an oxyvanadium cation is extracted in four countercurrent stages of mixer—settlers by a diesel oil solution of EHPA. Vanadium is stripped from the organic solvent with a 15 wt % sulfuric acid solution in four countercurrent stages. Addition of NH, steam, and sodium chlorate to the strip Hquor results in the precipitation of vanadium oxides, which are filtered, dried, fused, and flaked (22). Vanadium can also be extracted from oxidized uranium raffinate by solvent extraction with a tertiary amine, and ammonium metavanadate is produced from the soda-ash strip Hquor. Fused and flaked pentoxide is made from the ammonium metavanadate (23). 

Roles of Niobium Pentoxide, Vanadium Pentoxide and Titanium Dioxide In The Grain Growth And Sintering of Uranium Dioxide ,... 

The probable existence of protactinium was predicted as early as 1871 by Mendeleev to fill up the space on his peiiodic table between thorium (at, no. 90) and uranium (at. no, 92). He termed the unconfirmed element ekatantalum. In 1926, O. Hahn predicted the properties of the element in considerable detail, including descriptions of its compounds. In 1930, Aristid v. Grosse isolated 2 milligrams of what then was termed ekatantalum pentoxide and showed that element 91 differed m all reactions with comparable amounts of tantalum compounds with exception of precipitation by NH3. However, credit for the discovery of protactinium generally is attributed to Lise Meitner and Otto Hahn in 1917,... 

Titanium tetroxide Toluene 2,4-diisocyanate (TDI) Uranium hexafluoride Vanadium pentoxide Zinc chloride... 

The two chief oxides of uranium are the basic uranous oxide UO2 and the acid anhydride UO3. Intermediate between these two is a well-defined green oxide of composition UgOg. Less certain is the existence of a pentoxide UgOj, and a tetroxide, uranium peroxide, UO, though well-defined derivatives of the latter, peruranates, are known. 

The oxidation of acetaldehyde may also be carried out at temperatures of 80° to 100° C. by means of oxidation towers either in the presence or absence of a catalyst.127 Under these conditions peracetic acid is normally decomposed as rapidly as it is formed. Ill towers wetted with acetic acid and containing catalysts such as vanadium pentoxide, uranium oxide, roasted ferroso-ferric oxide, etc., the reaction between the aldehyde vapors and air tS"very rapid and complete, and temperatures as low as 30° to... 

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