Electrolytic reduction of Tc(VII) in nitric acid solution using glassy carbon electrode

グラッシーカーボン電極による硝酸溶液でのTc(VII)の電解還元

星 陽崇*; Wei, Y.*; 熊谷 幹郎*; 朝倉 俊英; 森田 泰治  

Hoshi, Harutaka*; Wei, Y.*; Kumagai, Mikio*; Asakura, Toshihide; Morita, Yasuji

グラッシーカーボン電極を用い、硝酸溶液中でTc(VII)の電解還元試験を行った。電解還元は-300mV(vs. Ag/AgCl)の定電位で実施した。電解還元前後のTc濃度がほとんど変化しなかったことから、TcOやTc等が電極表面へ析出しないと考えられる。吸光スペクトル測定及び陰イオン交換体を用いた吸着バッチ試験の結果から、Tc(VII)はTc(IV)に還元されることが、明らかとなった。

Electroreduction of Tc(VII) in nitric acid solution using grassy carbon electrode was studied. The electroreduction was conducted at a constant potential -300 mV (vs. Ag/AgCl) with a potentiostat. It was found that difference of the Tc concentration in the solutions before and after the electrolysis was negligibly small. This means that there were almost no TcO or Tc deposited on the carbon fiber electrode during the electroreduction. Absorption spectra and distribution coefficients obtained by ion-exchange analysis indicated that Tc(VII) was reduced to Tc(IV).