abstracts - Институт катализа им. Г.К. Борескова

OP-I-13MECHANISMS OF THE REDOX REACTIONS OVER HETEROGENEOUSNANOCATALYSTSSulman E., Matveeva V., Sulman M., Doluda V., Demidenko G., Ankudinova T.,Sidorov A., Bronstein L. 2 , Valetsky P. 1Department of Biotechnology and Chemistry, Tver Technical University, Tver, Russia1 A.N. Nesmeyanov Institute of Organoelement Compounds RAS, Moscow, Russia2 Chemistry Department, Indiana University, Bloomington, IN 47405, USAE-mail: sulman@online.tver.ruThe mechanism of fine chemistry reactions catalyzed by metal stabilized nanodispersionsis in focus of modern research programs. There are a lot of nanostructured polymeric systemsthat can control the nanoparticles growth, stabilize them and modify their surface due topolymer influence. Nanostructured catalytic systems of different types are synthesizeddepending on the method of the obtaining of polymeric nanocomposites containing metalsnanoparticles: (i) metal nanodispersions in amphiphilic block copolymer micelles nucleis, (ii)metal containing nanostructured polymers, (iii) metal nanoparticles impregnated in ultra thinlayers of polyelectrolytes supported on inorganic support. Physical and chemicalinvestigations show the possibility of transition metals nanoparticles formation with the meandiameter of 1-2 nm and low size distribution. Besides, the addition of the second modifyingmetal to the cluster containing the main catalytically active component leads to the change ofelectron density and surface geometry [1-6].These polymer based bi and mono metallic catalysts were used for the investigation ofthe mechanisms of selective oxidation of hydroxy, keto and aldehyde groups [1-3, 5] andselective hydrogenation of unsaturated substances [4, 6]. A number of physical and chemicalinvestigations of the synthesized nanocatalysts and substrates was fulfilled. The kineticpeculiarities of the processes of oxidation and reduction over different catalyst were studiedand substrate ratio, activation energies were determined. The mathematical models of thereactions were developed and the hypotheses were put forward. The kinetics investigation, thedata of physical and chemical analyses of catalytic systems show the possibility of theinteraction of the catalyst active component with solvent, support, modifier and substrate.According to obtained data, the oxidation and reduction reactions run through a polyligandreaction complex. The substrate activation is due to the electron density transfer from thecatalyst active component.The modification of the catalyst properties by the formation of a stabilizing film round aparticle is possible only for metal nanoparticles. This is the main advantage of such systems102