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Information × Registration Number 0224U032909, (0124U003775) , R & D reports Title New approaches to the kinetics of a heterogeneous catalytic process popup.stage_title Дослідження кінетики гетерогенно-каталітичних процесів гідрування та окислення. Теоретичний аналіз кінетичних схем досліджуваних реакцій Head Stryzhak Petro Ye., Доктор хімічних наук Registration Date 11-12-2024 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 To develop new approaches to the kinetics of heterogeneous catalytic processes, theoretical and experimental studies were conducted on the hydrogenation of organic compounds and the oxidation of carbon monoxide. A numerical solution of the reaction-diffusion equation is obtained in the form of the effectiveness factor, which takes into account the presence of external diffusion limitations of the observed rate of the process, for the kinetic equations of the bimolecular irreversible heterogeneous catalytic chemical reaction, which proceeds according to the associative and dissociative mechanisms of Langmuir-Hinshelwood and Eley-Rideal. The differences in the effectiveness factor make it possible to select a certain kinetic model of a heterogeneous catalytic process, which takes place under the condition of the presence of external diffusion limitations, among the set of other models that satisfactorily describe the rate of the heterogeneous catalytic reaction. The concentration dependence of the effectiveness factor which takes into account the presence of external diffusion limitations for the kinetic equations is obtained numerically for the catalysts of different geometric shapes under the condition of finite values of Sherwood number. Temperature and concentration dependences of the rate of ethylene and acetylene hydrogenation reactions are obtained experimentally under conditions of both excess hydrogen and excess ethylene and acetylene for the samples with C60 and C70 fullerenes deposited on alumina. It was found that the obtained dependencies of reaction rate on hydrogen concentration qualitatively differ from similar dependencies for the hydrogenation of organic molecules with molecular hydrogen under atmospheric pressure. Based on these studies, a mechanism of the process is proposed, as well as the kinetic equation is obtained, and its kinetic and thermodynamic parameters are calculated. Product Description popup.authors Bychko Ihor B. Zhokh Oleksii О. Karpenko Oksana S. Stets Vladyslav J. Stoliarchuk Iryna L. Trypolskyi Andrii I. popup.nrat_date 2024-12-11 Close