Dimethylsulfone, molten

Fig. 1 Voltammetric reduction ofThCU (2.6 X 10 M) in molten dimethylsulfone at 400 K (Pt cathode, scan rate = 0.1 V s , 0.25 M LiCi) (reprinted from Journai of Aiioys and Compounds, Vol. 228, L. Martinot,...

U(III) species and a second three-electron reduction to give U(0) metal. The first reduction, U(IV)/U(III) couple, is elec-trochemically and chemically irreversible except in hexamethylphosphoramide at 298 K where the authors report full chemical reversibility on the voltammetric timescale. The second reduction process is electrochemically irreversible in all solvents and only in dimethylsulfone at 400 K was an anodic return wave associated with uranium metal stripping noted. Electrodeposition of uranium metal as small dendrites from CS2UCI6 starting material was achieved from molten dimethylsulfone at 400 K with 0.1 M LiCl as supporting electrolyte at a platinum cathode. The deposits of uranium and the absence of U CI3, UCI4, UO2, and UO3 were determined by X-ray diffraction. Faradaic yield was low at 17.8%, but the yield can be increased (55.7%) through use of a mercury pool cathode. 

The brown hexacyanato complex (Ph4As)2[Re(CNO)6] has been reported to be the product of reaction K2ReCl6 with KOCN in molten dimethylsulfone followed by dissolution of the residue in... 

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