The review article shows the evolutionary path that turnover frequency (TOF) and turnover number (TON) have passed from “Boreskov`s Rule” to their modern definitions. From the equation catalysis rate, the second method for calculating TOF is obtained using the characteristics of catalyst material. Was prooved the possibility of obtaining TOF in two ways - using the characteristics of catalysis process and using the characteristics of the catalyst and reagents. The equivalence of two methods of TOF calculation is proved. It turned out that TOF is not a complete and unambiguous characteristic of the catalyst, as it was usually believed. TOF is only partially dependent on the characteristics of the catalyst material. It turned out that TOF is not a characteristic of a catalyst, but of a “catalyst + reagents” system, and its value directly depends on the state of their oxidation. It is proposed to use the list of oxidation states of chemical elements as the main tool in the selection of catalysts. The Sabatier principle limits the TOF and TON values by limiting the multielectron transitions when the oxidation state of the active sites of the catalyst changes. An explanation for the effect of overcoming the Sabatier prohibition is given, in which external synchronous action on the catalyst makes it possible to achieve a catalytic reaction speed higher than the Sabatier maximum.
The review article studies the role of trace elements in protecting the body from viruses and focuses on the high antiviral activity of trace elements, which they exhibit if they are in a low degree of oxidation. Trace elements in a degree of oxidation make it possible to create new generation of antiseptics safe for humans. Has been discovered the mechanism of antiviral action of trace elements in a low degree of oxidation based on the suppression of electrostatic Coulomb interaction of virus with the cell. Sanitizers of a new generation can become effective prophylactic means for protecting the body from infection COVID-19 due to the fact that a vaccine against the SARS-CoV-2 coronavirus is under development, and there are no direct drugs for it. Compositions of substances for pharmaceutical use based on antimicrobial trace elements in a low degree of oxidation, which can be used either directly or as raw materials for production of drugs against the SARS-CoV-2 coronavirus, are given. Aqueous solutions of trace element sanitizers are suitable for inhalation and intranasal application and can be used in the form of aerosol or spray for throat and nose or eye drops at the first symptoms of disease, as well as at high risks of infection.
The mechanism of heterogeneous catalysis taking into account the influence of temperature is briefly considered in the development of the concept "electron as a catalyst". Here the catalytic cycle includes the heat transfer and electron generation besides the mass transfer. The mechanism of temperature influence in heterogeneous catalysis is realised through the generation of electrons in a positive feedback loop. This mechanism involves the Edison and Seebeck thermoelectronic effects. The catalytic cycle of heterogeneous catalysis is supplemented with a thermoelectronic stage. The thermoelectronic stage of catalysis involves heat transfer and electron generation. Energy transfer to the active centre of the catalyst is an integral part of the catalytic cycle. Energy transfer is considered as a positive temperature feedback loop. The generation of electrons in the positive feedback loop and their transfer to the reactants leads to an increase in reactivity of the reactants. The positive temperature feedback loop leads to an exponential (sigmoidal) dependence of the reaction rate.
Abstract.The article explores a new type of catalysis - electric field catalysis. The laws of field catalysis are given. The characteristics of the electric field are determined, which set the values of the characteristics of the field catalysis. Field catalysis and field catalyst do not fit into the traditional definition of catalysis and catalyst, which may require a revision of the terminology of catalysis. The field is a more versatile catalyst compared to material catalysts, both in terms of its application to a wider range of chemical reactions, and in the ability to control the rate and selectivity. It is shown that a common donor-acceptor mechanism of catalysis is realized in heterogeneous and field catalysis. Generalized formulas are obtained, from which, as partial results, the laws of heterogeneous and field catalysis follow. New definitions of catalyst and field catalysis are given. The class of material catalysts has been expanded and supplemented with field catalysts.
Based on the generalization of experimental and theoretical studies in the field of catalysis, three basic laws of heterogeneous catalysis were discovered. From the formula of the catalysis rate law, the most important characteristics of catalysis are obtained - the reaction output, TOF and TON. Formulas for calculating the characteristics of catalysis using the characteristics of catalyst substance are given. A new concept of heterogeneous catalysis has been developed, in which the role of catalysts in the mechanism of accelerating chemical reactions has been revised. The oxidation states of the reactants and active sites of the catalyst are used as parameters in the formulas of the laws of catalysis. It follows from the laws of catalysis that oxidation states are such important characteristics of catalyst substance and reagents, that they directly affect the mechanism of catalysis itself and set the values of the most important characteristics of catalysis. As the main tool in the selection of catalysts, it is necessary to use the list of oxidation states of chemical elements known in chemistry. Based on the laws of catalysis, new definitions of catalyst and catalysis are given. The class of catalysts is expanded. Material catalysts are complemented by field catalysts. The substantiation of catalysis as a fundamental direction in science is given.
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