Kinetics of uranium (4) oxidation in nitric acid solution in the presence of technetium (4)

Spectrophotometric method was used to study kinetics of uranium (4) oxidation in nitric acid solution in the presence of technetium (4). The reaction is shown to be of zero order relatively uranium (4) concentration. Reaction rate is increased in proportion to nitrogen acid concentration. Reaction order relatively technetium (4) concentraion and hydrogen ions is respectively 0.7 and 1. The reaction activation energy in 4.0 mol/l nitric acid solution is 76 kJ/mol. Reaction mechaism including slow technetium (4) oxidation to technetium (5) by nitirc acid and fast uranium (4) oxidation by technetium (5) ions is suggested and discussed