[en] The Pt-catalyzed interaction between formic and nitric acids has been studied in the presence of 1% Pt/SiO₂. Kinetic and stoichiometric measurements were carried out under the following conditions: [HNO₃]₀ = 0.7-8 M; [HCOOH]₀ = 0.55-4.5 M; T = 55-85 C; liquid-to-solid ratio S/L = 0.1-0.02 g/ml. It was shown that in the presence of platinum catalyst the interaction between HCOOH and HNO₃ starts with confidence at 60-80 C without any induction period. Complex nature of the interaction between HCOOH and HNO₃ in the presence of platinum catalyst is revealed. It was found that the reactions of heterogeneous catalytic reduction of nitric acid and homogeneous autocatalytic denitration proceed simultaneously. A contribution of each process depends on the acidity and the total nitrate concentration in the solution. The order of the reaction with respect to [HCOOH] is 1. The order of the reaction with respect to (HNO₃) is 0 under the conditions when an autocatalytic accumulation of HNO₂ does not take place. It was found that the catalytic interaction between HCOOH and HNO₃ takes place in the presence of antinitrite agents as urea and hydrazine, though the rate of this process is not high. At the same time, the reaction of HCOOH catalytic decomposition does not proceed in non-nitrate media (under the conditions of the experiments). A method of the catalytic denitration was proposed for the reprocessing of aqueous radioactive waste. (orig.)