Trichloride, uranium

The tris cyclopentadienide complex of uranium was first prepared by the direct reaction of uranium trichloride with a benzene suspension of potassium cyclopentadienide. More recently it has been prepared by the reduction of tetra-... 

Uranium Trichloride, UCI3, may be obtained by heating uranous cliloride in hydrogen. It is a reddish-brown substance which readily... 

Acid uranous sulphates have been described, e.g. 112(804)4.112804, 11(804)2.112804.101120, and 1111(804)2. The latter, which separates in dark brown leaflets when a solution of uranium trichloride is added to concentrated sulphuric acid at 0° C., may contain trivalent uranium. 

The dark red UOCl was reported several years ago 192), the researcher having obtained it accidentally while subliming UCI3, probably owing to the reaction of the hot uranium trichloride with silica or some other oxide. 

Moody, D. C. Odom, J. D. "The Chemistry of Trivalent Uranium The Synthesis and Reaction Chemistry of the Tetra-hydrofuran Adduct of Uranium Trichloride, UCl3(THF)x,"... 

Til4[g] TITANIUM TETRAIODIDE (GAS) 1688 UCI3 URANIUM TRICHLORIDE 1734... 

UOCI3 URANIUM TRICHLORIDE OXIDE 1751 WCI2[gl TUNGSTEN DICHLORIDE (GAS) 1792... 

An efficient electrolysis process must run under substantially irreversible conditions, i.e. the gas evolved at the anode must be unable to react again, either directly or indirectly, with the rare metal product. To this end, the gas (usually chlorine) is often led away in a fairly direct manner without contacting the cathode. It is particularly important to avoid processes where the chlorine can effectively dissolve in the melt and subsequently migrate to the cathode. This might occur, for example, in the electrolysis of uranium trichloride, where the liberated chlorine is capable of reacting with excess uranium trichloride to form uranium tetrachloride, which is freely soluble in the melt. If the tetrachloride is allowed to diffuse to the cathode it can attack the uranium metal product to re-form uranium trichloride, i.e. 

Uranium, unlike thorium, has an accessible trivalent oxidation state. It has been shown that uranocene can be reduced by lithium naph-thalide to the bis([8]annulene)uranate(III) anion.23 The same complex can be synthesized by the reaction of two equivalents of [8]annulene dianion with one equivalent of uranium trichloride.23... 

We have found that [8]annulene dianion reduces uranium tetrachloride to uranium trichloride when the reaction is carried out at -78° C.2 t When two moles of [8]annulene dianion in THF are added to one mole of uranium tetrachloride in THF at -78° C, the green color of uranium tetrachloride changes to the purple color of the trichloride. As this reaction mixture is warmed slowly to room temperature, the color of the reaction changes to the dark green color of uranocene. The yield of uranocene is not affected in this method of reaction. When one-half molar equivalent of [8]annulene dianion is added to uranium... 

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