Direct Spectroscopic Determination of Europium（ Ⅱ ） Concentration During Europium（ Ⅲ ） Electro-Reduction in Hydrochloric Acid Medium

作     者：Ludek Jelinek Tsuyoshi Arai Wei Yuezhou Mikio Kumagai 

作者机构：Institute of Research and Innovation （IRI） 1201 Takada Kashiwa 277-0861 Japan 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2007年第25卷第1期

页      面：1-5页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 070301[理学-无机化学] 

基　　金：Project supported by Japan Society for the Promotion of Science (JSPS) 

主　　题：Eu( Ⅱ ) electroreduction hydrochloric acid UV spectroscopy rare earths 

摘      要：UV-Vis spectroscopy was used to directly determine the concentration of Eu（ Ⅱ） during electroreduction of Eu （ Ⅲ ） in hydrochloric acid medium. Electroreduction was carried out in a flow type electrolyzer with glassy carbon cathode at the constant potential of - 800 mV vs. Ag/AgCl. The effects of oxygen and concentration of hydrochloric acid on the system were investigated. For 0.01 mol· L^-1 hydrochloric acid, calibration curves for Eu （Ⅱ） absorption bands at 248 and 320 nm were constructed. Molar absorption coefficients were estimated to be 2016 and 648 L· mol^-1·cm^-1, respectively. The absorbance strongly decreased with decrease in pH of the solution, whereas concentration of chloride had only a negligible effect.