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Uranium minerals uranyl vanadates

The frequent occurrence of vanadium in uranium minerals renders the separation of these two metals of importance. One method in use is based on the solubility of uranyl nitrate in ether, %vhilst vanadic and also molybdic and tungstic acids are insoluble. A solution containing these substances may therefore be evaporated to drjmess, and the uranyl salt extracted from the residue with ether. Another method depends upon the fact that uranyl nitrate is readily soluble, whilst vanadium compounds are insoluble, in acetic acid of 95 per cent, strength to which nitric acid has been added in the proportion 1 20. ... [Pg.340]

The order of presentation of the uranium minerals will follow chemical groups. The U minerals are discussed first, followed by the niobates, tantalates and titanates. These two groups include the primary reduced minerals. The uranyl minerals are considered in the order hydrated oxides, silicates, phosphates and arsenates, vanadates, molybdates, sulphates, carbonates, and selenates and tellurates. Each section includes an evaluation of the known crystal chemistry and its effect on chemical variability and occurrence of mineral species. [Pg.43]

The uranyl vanadates form mineral groups distinct from the phosphates and arsenates because of the markedly different chemistry of the vanadium ion. Like uranium, vanadium shows several valence states in nature, and its detailed mineralogy is very complex. The crystal chemistry of vanadium was reviewed by Evans.In its lower valence states it forms distinct vanadium minerals, but in its higher valence state 5-1- it com-... [Pg.58]

Dominant ore minerals in the reduced zone are pitchblende and coffinite and, in some deposits, associated primary vanadium oxides—for example, montroseite. In oxidized zones the important uranium minerals are the uranyl vanadates (carnotite, tyuyamunite or francevillite). Accessory elements include Mo, Se and Cu. Average uranium content ranges from 0.01 to 0.40 7o U3O8. [Pg.126]


See other pages where Uranium minerals uranyl vanadates is mentioned: [Pg.489]    [Pg.59]    [Pg.242]    [Pg.891]    [Pg.546]    [Pg.891]    [Pg.294]    [Pg.7036]   
See also in sourсe #XX -- [ Pg.58 , Pg.59 , Pg.60 , Pg.61 ]




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Uranyl minerals

Vanadate minerals

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