کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
193768 | 459777 | 2007 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Reduction process of uranium(IV) and uranium(III) in molten fluorides Reduction process of uranium(IV) and uranium(III) in molten fluorides](/preview/png/193768.png)
This study focused on the electroreduction process of uranium cations in molten fluorides. It involved cyclic voltammetry, chronopotentiometry with and without current reversal, and square wave voltammetry.The results indicate a two-step reduction process for uranium(IV). The first step U(IV)/U(III) exchanging one electron corresponds to a soluble/soluble system and is limited by U(IV) diffusion with DU(IV) = 1.25 ± 0.35 × 10−5 cm2 s−1 in LiF–NaF at 720 °C.In order to perform a thorough study of the second step U(III)/U(0) in the reduction process, the melt was chemically reduced in U(III) with U metal as reducing agent. Alternatively to the use of LiF–NaF where U metal is unstable at 720 °C, the chemical reduction of U(IV) in U(III) was performed in a LiF–CaF2–UF4 solution containing U metal at 810 °C. It has been confirmed that the reduction of U(III) proceeds in one step exchanging three electrons and by a diffusion controlled process with DU(III) = 2.2 ± 0.7 × 10−5 cm2 s−1 in LiF–CaF2 at 810 °C.
Journal: Electrochimica Acta - Volume 52, Issue 12, 10 March 2007, Pages 3995–4003