Reaction Kinetics Between N,N-Dimethylhydroxylammonium Ion and Nitrous Acid in Nitric Acid

The reaction kinetics of N,N-dimethylhydroxylammonium ion(DMHAN) with nitrous acid were studied by spectrophotometerly in 0.1-0.4 mol/L nitric acid media. Influences of temperature, ion strength, nitric acid concentration, nitrous acid concentration and DMHAN concentration were investigated. The reaction rate equation is obtained as:
 -dc(HNO₂)/dt=kc^1.26(HNO₂)c^0.85(DMHAN)c^0.45(H⁺)
The reaction rate constant and the reaction activation energy are 3.09 (mol/L)^-1.56•s^-1 and 55.1 kJ/mol at 20 ℃, μ=0.50 mol/L, respectively. The stoichiometric ratio of nitrous acid to DMHAN is observed by 2.5∶1.