Nitrate ion and tributyl phosphate concentration dependence of europium extraction / back extraction rate in micro organic droplet / nitric acid solution system

Kusano, Yuka*; Miyagawa, Akihisa*; Nagatomo, Shigenori*; Nakatani, Kiyoharu*; Sano, Yuichi  

The solvent extraction / back-extraction process of europium with tributyl phosphate was kinetically analyzed from the microfluorescence measurement of micro organic droplets. From the rate constant dependence on nitric acid, nitrate ion, and tributyl phosphate concentrations, it was clarified that extraction is governed by the movement of europium with two nitrate ions at the organic-aqueous interface, and the quantitative relationship between the inverse extraction rate and these concentrations.