Uranyl chlorate

One last point. In the reaction of uranium(IV) where it is convenient to do a tracer experiment because there is only one metal ion product, we have actually determined the number of oxygens transferred to the uranyl ion product from the chlorite, and this number corresponds to 1.3 oxygen per chlorite transferred to the uranium. This is consistent with the results we reported some years ago (5) on the oxidation of uranium (IV) with Pb02 and Mn02, where indeed more than one oxygen is transferred. In conclusion, we feel that we have some direct evidence for two-electron transfer in these reactions and the formation of a chlorine(I) intermediate followed by the formation of chlorate. 

Uranyl Acetate. U02(C2 0. 21 0 mw 422.19 yel rhomb crysts mp 110° (-2H20) bp 275° (decompn) d 2.893g/cc at 15°. V sol in ethanol sol in w. Prepn is by reacting Na acetate with U nitrate. The acetate has been suggested by DeMent (Ref 2) for use in a pyrot radioactive smoke formulation. The compn consists of U acetate 3, Na chlorate 8, S 4 and amm acid fluoride 4.5p, which upon ignition bums in a flameless reaction generating a grey smoke... 

Uraayl Chlorate, U02(ClO3)2.xH2O, is obtained by the addition of barium chlorate to a solution of uranyl sulphated After filtration and evaporation, crystals are obtained which are readily soluble in water,... 

Barium Diuranate, BaUjO, is obtained by heating barium uranyl acetate, or by heating together the green oxide and barium chlorate. It is obtained in a hydrated condition when ammonia is added to mixed solutions of barium chloride and uranyl nitrate, or when excess of baryta water is added to uranyl nitrate solution. It is a deep yellow crystalline powder. 

To leach the more acid-resistant minerals containing tetravalent uranium, steam is fed to the second tank to bring the temperature to 49 to 60°C, and sodium chlorate NaQOj is added to bring the oxidation-reduction potential e, measured relative to the calomel electrode, to from —0.47 to —0.51 V. At —0.51 V, the equilibrium ratio of ferric iron to ferrous iron in the solution is 0.52. Ferric iron catalyzes the oxidation of insoluble tetravalent uranium to the soluble hexavalent uranyl form ... 

Measurements of nitrate in soils and waste waters using the TOAN-DBP electrode and the brucine method agreed closely. All these nitrate ISEs (66,67) are subject to serious interference from iodide, chlorate and perchlorate. This feature can in turn be exploited, e.g., the Corning nitrate exchanger may be readily converted to a viable chlorate-sensing cocktail using an extraction technique as described for the uranyl phosphate sensor (section 3.2.10). 

More then 150 minerals containing uranium are known. Typically, however, uranium ores contain only about 0.1% uranium. In the commercial production of uranium metal, the ore is crushed, concentrated, roasted, and in most cases leached with sulfuric acid in the presence of an oxidizing agent such as manganese dioxide or chlorate ions to convert all of the uranium to uranyl sulfato complexes. Carbonate leaching is used to extract uranium from ores containing minerals such as calcite. The recovery of uranium... 

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