ANALYSIS OF STOICHIOMETRIC REGULARITIES LIMITING STATIONARY STATES OF REACTION-RECTIFICATION PROCESSES

Development and improvement of industrial technologies based on the principle of combining reaction and mass exchange processes is an urgent task. This is due to their advantage over the traditional sequential way of performing the chemical transformation and separation of the resulting reaction mixture. In reaction-rectification processes, the conversion of the process, the rate of reaction and selectivity may be increased due to continuous withdrawal of the formed products from the reaction zone. In addition, capital and energy costs in such processes are significantly reduced due to the reduction or even complete absence of external recycling in them. The modern method of developing reaction-rectifying processes is the analysis of statics, which allows isolating the limiting stationary states corresponding to the maximum yield of the target product. An essential disadvantage limiting the possibility of using this method for solving practical problems is the consideration of a single chemical reaction in its framework. At the same time, when passing to real processes, as a rule, this restriction is violated. The article offers a number of original approaches designed in the form of an algorithm that allows the analysis of statics to be extended to reaction-rectification processes with an unlimited number of components forming the reaction mixture and an unlimited number of chemical reactions taking place between them. On the basis of this algorithm, a ChIM program was developed in the SciLab environment, which makes it possible to single out sets of limiting stationary states of a combined process characterized by maximum reagent conversion values, selectivity and yield of the target product. The procedure for using the ChIM program is illustrated by the example of the industrial process for obtaining mesityl oxide from acetone. Calculations conducted using the software package Aspen Plus proved the possibility of practical implementation of limiting stationary state providing the maximum yield of mesityl oxide, which was predicted by using of ChIM.

reaction-rectification processes, statics analysis, mesityl oxide, balanced polyhedron, manifold of chemical interaction, algorithm for constructing a reaction polyhedron

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