ReO_(4)^(-)在H_(2)SO_(4)和HNO_(3)体系中的电化学行为  

Electrochemical Behavior of ReO_(4)^(-) in Sulfuric Acid and Nitric Acid Media

作　　者：邓怡琳 张虎[1] DENG Yi-lin;ZHANG Hu(China Institute of Atomic Energy,P.O.Box 275(26),Beijing 102413,China)

机构地区：[1]中国原子能科学研究院放射化学研究所,北京102413

出　　处：《核化学与放射化学》2022年第3期356-361,I0007,共7页Journal of Nuclear and Radiochemistry

基　　金：国家自然科学基金资助项目(U1867205,21790371)。

摘　　要：在动力堆乏燃料中,^(99)Tc是主要的裂变产物之一,它的半衰期长达2.13×10^(5)a,对生态环境有长期危害,是PUREX流程非常关注的核素。Re的化学性质与Tc相似,研究Re的电化学行为,对了解Tc的化学性质具有很好的参考价值。本工作研究了H_(2)SO_(4)、HNO_(3)介质中ReO_(4)^(-)在铂电极上的电化学行为。在H_(2)SO_(4)和HNO_(3)体系中,循环伏安和控制电位电解库仑的测试结果表明,ReO_(4)^(-)在铂电极上的还原是一个多步的电子转移过程,会在铂电极上生成沉积层ReO_(2),此时会建立起电对ReO_(4)^(-)/ReO_(2)。在HNO_(3)体系中,当HNO_(3)浓度为1.00 mol/L时,ReO_(4)^(-)的还原过程与H_(2)SO_(4)体系中相似,当HNO_(3)浓度为2.00、4.00 mol/L时,HNO_(3)通过电化学还原产生HNO_(2),HNO_(2)氧化溶液中的低价Re。^(99)Tc is one of the main fission products in nuclear spent fuel in power reactor.Its half-life period is 2.13×10^(5) years,which has long-term harm to the ecological environment,and it gets special attention in PUREX process.The chemical properties of rhenium are similar to technetium.Studying the electrochemical behavior of rhenium is of great reference value for understanding the chemical properties of technetium.The electrochemical behavior of perrhenate in sulfuric acid and nitric acid on platinum electrode is studied.The results of cyclic voltammogram and bulk electrolysis with coulometry show that the reduction of ReO_(4)^(-) ions on the platinum electrode is a multi-step electron transfer process,and ReO_(2) is deposited on Pt electrode.Then the redox reaction of ReO_(4)^(-)/ReO_(2) will be established.In nitric acid,when the concentration of nitric acid is 1.00 mol/L,the reduction process of ReO_(4)^(-) is similar to that in sulfuric acid system.When the concentration of nitric acid is 2.00,4.00 mol/L respectively,nitric is reduced to nitrite by electrochemical reduction,which oxidizes the low valence state rhenium in solution.

关 键 词：ReO_(4)^(-) 铂电极 循环伏安曲线 控制电位电解库仑 

分 类 号：TQ150.1[化学工程—电化学工业]