钌是一种裂变产物，具有两种寿命相对较长的同位素103 Ru 和106 Ru，这两种同位素都是乏核燃料后处理过程中高活性 (HA) 废物萃余液的一部分。在再加工过程中，可能以 RuNO 3+络合物的形式存在的钌会遇到有利于挥发的温度。由于钌的高比放射性，了解挥发发生的机制非常重要。在这里，我们使用组合 CV、RDE 和电化学微重实验来研究 RuCl 3系统第一次。我们这样做是为了建立无 NO 的 Ru(III) 基线行为，以支持未来对 NO 络合钌的研究。使用宽水溶剂窗口碳电极，我们观察到溶液相 Ru(III)-Ru(IV)-Ru(III) 三聚体、固体 RuO 2和挥发性 RuO 4的离散氧化。我们还观察到固体RuO 2的离散还原回到Ru(III) 和Ru(III) 还原为钌金属。
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Ruthenium Volatilisation from Reprocessed Spent Nuclear Fuel – Studying the Baseline Thermodynamics of Ru(III)
Ruthenium is a fission product possessed of two relatively long lived isotopes, 103Ru and 106Ru, both of which form part of the Highly Active (HA) waste raffinate during spent nuclear fuel reprocessing. During reprocessing ruthenium, which may be in the form of the RuNO3+ complex, encounters temperatures conducive to volatilization. Due rutheium’s high specific radioactivity it is important to understand the mechanism by which volatilisation occurs. Here we use combined CV, RDE and electrochemical microgravimetry experiments in a study of the the RuCl3 system for the first time. We do this in the interest of establishing NO-free Ru(III) baseline behaviour so as to support future studies on NO complexed ruthenium. Using wide aqueous solvent window carbon electrodes we have observed discrete oxidations to a solution phase Ru(III)–Ru(IV)–Ru(III) trimer, to solid RuO2 and volatile RuO4. We have also observed and assigned discrete reductions of solid RuO2 back to Ru(III) and Ru(III) reduction to ruthenium metal.