The urea decomposition is the process of the heterogeneous cataolytic denitration of nitric acid solutions Part II.Reaction's products and stoichiometry.

摘要

The reaction products and the stoichiometry of the urea catalytic decomposition in the system HNO_3-HCOOH-Pt/SiO_2 were studied with an application of the IR spectroscopy,the mass spectroscopy methods and chemical analysis.It was found that in the presence of 0.1 g ml~-1 % Pt/SiO_2,the 0.1-0.4 M(NH_2)_2CO decomposes at 50-90 deg C in the solutions of 2.5-6.4 M HNO_3 containing 0.25-1.5 M HCOOH according to a stoichiomethric equation:3(NH_2)_2CO+3HCOOH+5HNO_3->~Pt2N_2+N_2O+2NH_4NO_3+NH_2CHO+5CO_2+6H_2O.Soluble reaction products-the ammonium nitrate and the formamide-undergo further a gradualdegradation under the conditions of a catalytic denitration reaction that starts when the urea decomposition is completed.