SYNTHESIS OF METALPORPHYRIN CATALYSTS AND THEIR CATALYTIC PROPERTIES IN HYDROGEN PEROXIDE DISPROPORTIONATION REACTION

The paper proposes a new method for the synthesis of metal-porphyrin complexes of iron, cobalt, manganese, vanadium from a petroleum porphyrin extract. Extraction of petroleum porphyrins from asphaltenes was carried out using bifunctional (ketone-alcohols) extractants proposed by us earlier. The isolated mixture of metalporphyrins is firsts demetallized with hydrochloric acid. As a result of this treatment, oil metalporphyrin complexes decompose into the corresponding porphyrine and metal ion. Further complexes is neutralized with alkali to pH=6-8 in order to obtain oil porphyrine. At the third stage phenyl sodium is added is excess to the isolated porphyrine and then sodium porphyrin complexes were treated with a salt of the required metal (Fe, Mn, Co, Ni) to obtain individual metal complexes. The physicochemical properties and structure of the synthesized complexes were studied. Their catalytic properties in the decomposition reaction of hydrogen peroxide in the DMFA-KOH-H2O system have been investigated. The experimental values of the H2O2 decomposition rate and the catalytic activity of the synthesized metal-porphyrin complexes have been obtained. The electronic spectra of obtaining samples were studied depending on the concentration of the catalyst at different temperatures, and a bathochromic shift of 9-13 nm of absorption bands was established upon the addition of hydrogen peroxide. The catalytic effect of various metal porphyrin complexes in the reaction of hydrogen peroxide decomposition was studied by volumetric method. The constructed dependences of the volume of released oxygen on time made it possible to establish that in the presence of metal porphyrin catalysts, the reaction of hydrogen peroxide decomposition proceeds much faster