THE KINETIC STUDY ON U(IV)-U(VI) ISOTOPIC EXCHANGE REACTION Ⅰ.THE CATALYTIC EFFECT OF Fe~(21) IN THE U(IV)-U(VI) ISOTOPIC EXCHANGE REACTION

The kinetics of the U(IV)-U(VI) isotopic exchange reaction was studiedwith ~(233)U as tracer in hydrochloric acid of high concentration. The catalytic effectof Fe~(2+) in the U(IV)-U(VI) isotopic exchange reaction was observed in thepresence of hydrochloric acid of high conentration. The exchange rate was foundto be accelerated by 10~2 times because of the addition of Fe~(2+). The activationenergy was calculated to be 73. 6 kJ/mol for the Fe~(2+) catalyzed U(IV)-U(VI)isotopic exchange reaction. This value is much smaller than that of 134.6 kJ/molwhich was found in the non-catalytic reaction.