Основы адсорбционных процессов

Abstract

The processes of sorption (adsorption, absorption) are an essential part of the closed cycle that takes place in sorption and adsorption heat pumps. The problems of dynamics and thermodynamics of adsorption are constantly given due attention. A huge variety of properties of real sorbents, as well as numerous adsorbents, the existence of a whole hierarchy of interrelated factors that affect adsorption processes, indicate the complexity of the solutions to this problem. Therefore, the study of the dynamics of physicochemical processes occurring in various types of thermal transformers is often solved in the first approximation or when one of the active factors is taken into account. The purpose of the study is the development of a method for analyzing adsorption processes and the field of application of adsorption in engineering. The problem of the theory of adsorption, as a rule, consists in determining the equilibrium condition of the system on the basis of available information on the properties of adsorbents and solution components. One of the ways is to formulate and solve a mathematical model of the dynamics of the analyzed phenomenon, including taking into account the effective interaction of the adsorbent-adsorbate complex. A big role in adsorption processes is played by temperature. The regularity of the dependence of adsorbate on the thermodynamic characteristics of the adsorption system is analyzed. The current state of the theory of adsorption makes it possible to carry out with a sufficient degree of accuracy a priori calculations of adsorption equilibria for various types of one- and two-component adsorption systems. One of the characteristic phenomena that occur in adsorption heat pumps is the diffusion of the agent. General regularities of diffusion in an inhomogeneous medium and porous sorbents are considered. If the medium consists of several components with different sorption properties, then it is necessary to take into account the adsorption potentials of the components. The study assumed the assumption that the concentration of diffusing molecules is small, and therefore we can neglect the interactions between them. In addition, the medium is assumed to be isotropic. The problem of determining the sorption and desorption time is solved. The equations obtained allow us to determine the required temperature T 2 from the value of the initial temperature T 1 with the required (3 ... 5%) error.