Reaction Kinetic Between Hydroxylamine Nitrate and Fe³⁺ by Measuring Potential of Fe³⁺/Fe²⁺

The kinetic study of the reaction between hydroxylamine nitrate(HAN) and Fe³⁺ in nitric acid solution was performed by measuring the potential of Fe³⁺/Fe²⁺. The effects of the concentration of HAN, the concentration of nitric acid, ionic strength, temperature and the concentration of Fe³⁺ on the reaction rate were also studied. The apparent rate equation may be expressed as follows: -dc(Fe³⁺)/dt＝kc^0.62(HAN)c^-2.80(H⁺)c(Fe³⁺)c^-0.85(Fe²⁺)The apparent rate constant is (2.9±0.1)×10^-6(mol/L)^3.02/s at 50℃ and I＝1.0 mol/L and the apparent reaction activation energy is (125±3)kJ/mol. NO₃^- can depress the reaction and increasing ionic strength can promote the reaction.