Thermodynamics of Irreversible Processes in an Isothermal Catalyst Grain

Numerical analysis of local and total entropy production in the simplest linear and nonlinear reaction-diffusion systems depending on boundary conditions and initial conditions has been carried out. It is shown that the results of calculations for linear and nonlinear differential equations at large values of the equilibrium constant do not differ practically. It is found that the total entropy production in the system is not a functional of the solution of the problem possessing extreme properties. As a selective potential possessing extreme properties, one can use the entropy production in the system only due to one of the irreversible processes – diffusion or reaction.