Temperature Dependence of Isotope Effects in Uranium Chemical Exchange Reactions

概要

論文の詳細を見る
Temperature dependence of isotope effects in U(IV)–U(VI) exchange reaction was experimentally studied by means of redox chromatography using columns packed with anion exchange resin in the temperature range 87–160°C (360–433 K). The experimentally observed isotopic separation coefficient, ε, was converted to the isotopic equilibrium constant, lnK=εo, of the U(IV)–U(VI) exchange reaction with the aid of the experimentally measured ionic mole fractions of U(IV) and U(VI) in the resin phase and the aqueous solution phase. The plots of εo vs. 1⁄T led to the temperature dependence of εo=0.69⁄T−82⁄T2, where the first term is due to the nuclear field effect (nuclear-electron interaction effect) and the second term is due to the molecular-vibration mass effect. The discussion is extended to the temperature dependence of the previously reported isotope effects in the U(III)–U(IV) electron exchange reaction, and the U(VI)-malate-complex ligand exchange reaction.
社団法人日本原子力学会の論文
2006-04-25