The kinetics of disproportionation of hydrogen peroxide in the presence of palladium(II)porphyrins with regularly changing macroring structures
摘要:
The kinetics and spectral manifestations of alkaline decomposition of H2O2 in a water-dimethylformamide medium catalyzed by (PdP)-P-II (P is the dianion of octaethylporphyrin and its monophenyl, 5,15-diphenyl,5,10-diphenyl, triphenyl, and tetraphenyl derivatives substituted at meso positions) was studied over a wide range of reagent concentrations under polythermal conditions. A complete kinetic description of the reacting systems was given, and the rates and set of elementary reactions, intermediate compounds, and kinetically significant equilibria were determined. The ion-molecular mechanism of hydrogen peroxide decomposition was substantiated. According to this mechanism, the only stable radicals involved in the reaction are the pi radical cation forms of palladium(II)porphyhrin catalysts.
Modifications in structure of palladium(II) porphinate as a method of regulating the catalysis of hydrogen peroxide decomposition
摘要:
Results of kinetic, volumetric, and spectral study of the reaction of alkaline H2O2 decomposition in a water-dimethyl formamide medium catalyzed by (PdPf)-P-II (P-f is octaethylporphyrin and its monophenyl-, 5,15-diphenyl-, 5,10-diphenyl-, triphenyl-, and tetraphenyl-substituted in meso-positions derivatives) under polythermal conditions are presented. It was found that the catalysis is of the heterogeneous nature; intermediates and complete kinetic characteristics (rates, activation parameters, and the orders with respect to all reagents) were determined depending on the macrocycle structure. The sequence of the catalytic activity of palladium(II) porphyrinates was estimated.