ABSTRACT
Transport of molecules through porous materials is carried out by a variety of flow mechanisms. Except for the Knudsen vapour flow, dense vapors and/or liquid phase take part in the discussed mechanisms. The construction of the kinetic equation for the local concentration of molecules results in a large increase in the order of the unknown correlation functions on the right side of the equation. In the discrete version of the theory on the basis of the lattice-gas models (LGM) the system of kinetic equations has a high dimension, so in practice, it is necessary to limit the minimal dimension preserving the effects of correlations between the molecules. If there are macroinhomogeneities, to calculate the flows it is necessary to separate homogeneous regions and complement the diffusion equation by appropriate boundary conditions. The kinetic equations of the LGM can be used to consider any relation between the characteristic times of migration atoms in a solid, adsorbed particles and chemical reactions.
