Details

Autor(en) / Beteiligte

• Uehara, Akihiro
• Shirai, Osamu
• Fujii, Toshiyuki
• Nagai, Takayuki
• Yamana, Hajimu

Titel

Electrochemical deposition of uranium oxide in highly concentrated calcium chloride

Ist Teil von

• Journal of applied electrochemistry, 2012-06, Vol.42 (6), p.455-461

Ort / Verlag

Dordrecht: Springer Netherlands

Erscheinungsjahr

2012

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The coordination circumstances and redox reactions of UO 2 2+ in the aqueous solution concentrated by calcium chloride, such as CaCl 2 ·6H 2 O (6.9 M CaCl 2 ), were studied by Raman spectroscopy and electrochemical methods. The frequency of the O=U=O symmetrical stretching vibration suggested that the complex formation of UO 2 2+ with Cl − leads to the weakening of U=O bond. In the electrochemical measurements, two-step cathodic currents were observed at −0.090 and −0.4 V (vs. Ag|AgCl) corresponding to the reduction of UO 2 2+ to UO 2 + and that of UO 2 + to UO 2 , respectively. It was found that UO 2 + formed at first cathodic current was disproportionated to form UO 2 2+ and UO 2 . The UO 2 was identified by X-ray diffraction analysis. Electrolytic deposition of UO 2 was observed in 6.9–4.7 M CaCl 2 and in 14 M LiCl. When small amount of proton, i.e., 0.005 M was coexisted in 6.9 M CaCl 2 , UO 2 2+ was reduced to form U 4+ instead of UO 2 .