【摘要】 用分光光度法研究了ｃ（ＣＨ３Ｎ２Ｈ３）、ｃ（ＨＮＯ３）、ｃ（ＵＯ２＋２）、ｃ（ＨＮＯ２）、离子强度和温度等因素对Ｎｐ（Ⅵ）还原速率的影响。求出了Ｎｐ（Ⅵ）还原反应级数和不同反应条件下的表观反应速率常数，建立了反应速率方程式。温度为２４℃时，还原反应的表观反应速率常数ｋ２＝６１．３ｍｉｎ－１。反应的活化能为（５９．６２±１．１２）ｋＪ·ｍｏｌ－１。提高单甲基肼浓度，降低ＨＮＯ３浓度和升高温度有利于加快Ｎｐ（Ⅵ）的还原；离子强度和ＵＯ２＋２浓度对反应速率无明显影响；当反应体系中有ＨＮＯ２存在时，Ｎｐ（Ⅵ）还原速率明显提高。更多还原

【Abstract】 Effects of c (CH 3N 2H 3), c (HNO 3), c (UO 2+ 2), c (HNO 2),ionic strength and temperature on reduction rate of Np(Ⅵ) are investigated.The results show that increasing concentration of monomethylhydrazine,decreasing concentration of HNO 3 and rising temperature are favorable to accelerate the reduction rate of Np(Ⅵ).The reduction rate equation of Np(Ⅵ) is obtained. The apparent rate constants and activation energy of the above reaction are calculated.The order of the reaction relative to monomethylhydrazine and HNO 3 equal to 1 and -1,respectively. Effects of ionic strength and concentration of UO 2+ 2 on reduction rate are negligible.If HNO 2 is present in the system,the reduction of Np(Ⅵ) to Np(Ⅴ) is accelerated.更多还原