Pu催化HNO<sub>2</sub>氧化U(Ⅳ)的研究

Pu催化HNO₂氧化U(Ⅳ)的研究

摘要: 研究了Pu存在条件下HNO₂氧化U(Ⅳ)的反应，并考察了HNO₂浓度、反应温度、HNO₃浓度、Pu浓度对U(Ⅳ)氧化速率的影响。结果表明：Pu对HNO₂氧化U(Ⅳ)的反应具有显著催化作用；获得了Pu催化条件下HNO₂氧化U(Ⅳ)的动力学方程：-dc(U(Ⅳ))/dt=kc(U(Ⅳ))c^1.3(HNO₃)c^1.3(NO^-₂)，得到了29℃时的反应速率常数k=(0.69±0.04) L^2.6/(mol^2.6•min)。并对反应历程进行了探讨。

Abstract: The oxidation of U(Ⅳ) by nitrous acid in the present of plutonium was studied. The influence of the concentration of nitrous acid, nitric acid, plutonium on the oxidation of U(Ⅳ) was investigated. The results show that plutonium can catalyze the reaction between U(Ⅳ) and nitrous acid. And the rate equation of the reaction between U(Ⅳ) and nitrous acid catalyzed by plutonium was obtained: -dc(U(Ⅳ))/dt=kc(U(Ⅳ))c^1.3 (HNO₃)c^1.3(NO^-₂), k=(0.69±0.04) L^2.6/(mol^2.6•min) when the temperature was 29 ℃. The mechanism of the oxidation of U(Ⅳ) was discussed.