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Information × Registration Number 0225U004544, (0124U003775) , R & D reports Title New approaches to the kinetics of a heterogeneous catalytic process popup.stage_title Встановлення механізмів досліджуваних процесів та теоретичний аналіз впливу макрофакторів на їх кінетику Head Stryzhak Petro Ye., Доктор хімічних наук Registration Date 11-12-2025 Organization L. V. Pisarzhevskii Institute Of Physical Chemistry of The National Academy of Sciences of Ukraine popup.description1 The goals of the project are to create new approaches to the analysis of the kinetics and mechanisms of a heterogeneous catalytic reaction; to determine the possibility of a kinetic description using the effect of the catalyst surface microstructure (fractality); effect of the macrokinetic factors (reactant transport to and in the catalyst particle) on the process rate; determination of the possible new ways to activate substrates in the reaction of their hydrogenation on carbon nanomaterials. popup.description2 Based on the experimental and theoretical results obtained at the intermediate stage of the project, mechanisms and corresponding kinetic equations for ethylene and acetylene hydrogenation reactions on carbon nanomaterials were proposed for the first time. The main conclusion is that the kinetics of hydrogenation of unsaturated hydrocarbons on carbon nanomaterials is not described using existing hydrogenation mechanisms, such as the Horiuti-Polanyi mechanism, and requires determination of the dependence of the induced hydrogen adsorption constant and surface hydrogen migration on the hydrogen partial pressure. As a result of the implementation of the intermediate stage of the project, numerical and analytical solutions of the reaction-diffusion equation were obtained. The latter is based on kinetic equations established in the frame of the Langmuir-Hinshelwood and Langmuir-Rideal mechanisms and takes into account the presence of external and internal diffusion limitations for the transport of reagents, and also non-isothermal conditions of the heterogeneous catalytic reaction. Based on the application of the obtained solutions, the dependence of the effectiveness factor on the parameters of a heterogeneous catalytic process were obtained, which will be used to discriminate kinetic models of the heterogeneous catalytic reactions. This method of discrimination of kinetic models differs from existing approaches in that it takes into account the physical processes of heat and mass transfer, and not only the statistical analysis of kinetic constants or the calculation of information criteria, e.g., the Akaike criterion. The kinetics of the heterogeneous catalytic oxidation of CO in the presence of samples of massive porous silicate catalysts with different internal surface morphology were studied and kinetic parameters were obtained. Product Description popup.authors Andrew I. Trypolskyy Igor B. Bychko Olexiy О. Zhokh Oksana S. Karpenko Iryna L. Stolyarchuk Vitaliy J. Stets popup.nrat_date 2025-12-11 Close