摘要
采用分光光度法研究了HNO3溶液中U(Ⅳ)还原Np(Ⅴ)的反应,获得了动力学方程-dc(Np(Ⅴ))/dt=kc(Np(Ⅴ))c0.7(U(Ⅳ))c1.9(H+)c(NO-3),25℃时反应速率常数k=(6.37±0.49)×10-3 L3.6/(mol 3.6·min),反应活化能Ea=60.13kJ/mol。结果表明,浓度为0~4.2×10-2 mol/L的U(Ⅵ)对U(Ⅳ)还原Np(Ⅴ)的反应几乎没有影响,并探讨了可能的反应机理。
The reduction of NpO2+ to Np4+ by U(Ⅳ) in nitric acid solution has been studied by spectrophotometric method,and the rate equation is described by:-dc(Np(Ⅴ))/dt=kc(Np(Ⅴ))c0.7 (U(Ⅳ))c1.9 (H+) c (NO3-)where k=(6.37±0.49)× 10-3 L3.6/(mol3.6 · min) at 25 ℃.The activation energy is estimated to be 60.13 kJ/mol.U(Ⅵ) with the concentration of 0-4.2× 10-2 mol/L has little effect on the reaction.The possible mechanism is discussed.
出处
《核化学与放射化学》
CAS
CSCD
北大核心
2013年第6期346-350,共5页
Journal of Nuclear and Radiochemistry