氨基羟基脲与Np(Ⅵ)的还原动力学  

Kinetics of Reaction Between Np(Ⅵ)and Hydroxysemicarbazide in Nitric Acid Solution

作　　者：王妍 肖松涛[1] 兰天[1] 刘协春[1] 欧阳应根[1] 李辉波[1] WANG Yan;XIAO Song-tao;LAN Tian;LIU Xie-chun;OUYANG Ying-gen;LI Hui-bo(China Institute of Atomic Energy, P. O. Box 275(26), Beijing 102413, China)

机构地区：[1]中国原子能科学研究院放射化学研究所,北京102413

出　　处：《核化学与放射化学》2018年第6期359-365,共7页Journal of Nuclear and Radiochemistry

基　　金：中国核工业集团公司武器装备预先研究基金资助项目(61601090401)

摘　　要：研究了氨基羟基脲(HSC)浓度、H^+浓度、NO_3^-浓度、Fe3+浓度、UO2+2浓度、反应温度对氨基羟基脲与Np(Ⅵ)还原反应速率的影响,获得了其动力学方程。实验结果表明:增加氨基羟基脲浓度和提高反应温度,降低H^+浓度和NO_3^-浓度,可以提高氨基羟基脲与Np(Ⅵ)还原速率;在UO2+2存在或Fe3+浓度小于1×10-3 mol/L时,对氨基羟基脲与Np(Ⅵ)的还原没有明显影响。氨基羟基脲还原Np(Ⅵ)的动力学方程式为:-dc(Np(Ⅵ))/dt=kc(Np(Ⅵ))c2.52(HSC)c-0.53(H+)c-0.61(NO_3^-),在4.00℃时k=(1 037±60)(mol/L)-1.40·s-1,活化能Ea=(64.03±6.4)kJ/mol。The effects of c(HSC),c(H^+),c(Fe^3+),c(UO2^2+),ionic strength and temperature on the reduction rate of Np(Ⅵ)by hydroxysemicarbazide(HSC)were investigated.The results show that Np(Ⅵ)can be rapidly reduced to Np(Ⅴ)by HSC.The reaction rate of Np(Ⅵ)with HSC can be accelerated by increasing concentration of HSC and temperature,decreasing concentration of HNO3and ionic strength.The kinetic equation for the reduction of Np(Ⅵ)by hydroxysemicarbazide is:-d c(Np(Ⅵ))/d t=kc(Np(Ⅵ))c^2.52(HSC)c^-0.53(H+)·c^-0.61(NO3^-)where k=(1037±60)(mol/L)^-1.40·s^-1at4.00℃.The activation energy is E a=(64.03±6.4)kJ/mol.No significant effect on the reduction of Np(Ⅵ)by hydroxysemicarbazide is observed when the concentration of Fe^3+is less than1×10^-3mol/L or in the presence of UO2^2+.

关 键 词：Np(Ⅵ) 氨基羟基脲 还原反应 反应速率 

分 类 号：TL241.1[核科学技术—核燃料循环与材料]