Reaction Kinetics of Mono-methylhydrazine With Nitrous Acid in Nitric Acid Medium

The oxidation of mono-methylhydrazine (MMH) with nitrous acid in nitric acid medium was researched. The rate equation was determined as follows: －dc(HNO2)/dt=kc(H+)c1.1(NO－3)c1.1(MMH)c(HNO2). The k is (115±2) (mol/L)－3.2•s－1 and the corresponding activation energy Ea is (37.8±0.1) kJ/mol with the nitrate concentration of 0.50 mol/L at the temperature of 2.6 ℃. The result indicates that the oxidation of MMH with nitrous acid is fast. The increase in the acidity and the concentration of MMH or NO－3 can speed the reduction of nitrous acid.