DYNAMICS OF TWO-STAGE CATALYTIC REACTIONS WITH NON-IDEAL KINETICS

The dynamics of two-stage catalytic reactions occurring quasi-steady-state for the main substances (reagents) according to the typical two-stage Temkin and Bonhoeffer-Farkash mechanisms was investigated in an open isothermal gradientless system with the Marcelin-De Donde kinetic law. The Marcelin-De Donde kinetic law takes into account the non-ideality of the reaction medium by expressing the reaction rate through the chemical potentials of intermediate substances, which linearly depend on the concentrations and mutual influence of these substances. The level of mutual influence of intermediate substances was determined by a combination of the values and signs of the non-ideality coefficients (there is no mutual influence of intermediate substances - zero non-ideality; the mutual influence is the same - single-level non-ideality; limited mutual influence of intermediate substances is different - two-level non-ideality; unlimited mutual influence of intermediate substances - arbitrary non-ideality). Relationships have been established for calculating the linear and nonlinear relaxation times that characterize the specifics of the transition process during movement to a steady state of catalytic reactions occurring according to the Marcelin-De Donde kinetic law at various levels of non-ideality of the reaction medium. It is shown that the relaxation characteristics found differ from the corresponding relaxation characteristics corresponding to the ideal kinetic law of acting masses. Examples are given of using the obtained relaxation characteristics to solve direct and inverse problems of chemical kinetics related to estimating the frequencies of reaction stage rates taking into account the non-ideality of the reaction medium. It has been established that changing the level of non-ideality of the reaction environment makes it possible to regulate the rate and duration of catalytic processes. For citation: Kol'tsov N.I. Dynamics of two-stage catalytic reactions with non-ideal kinetics. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2025. V. 68. N 6. P. 59-69. DOI: 10.6060/ivkkt.20256806.7176.