Diffusion and electromigration of ions -- products of the proton exchange reaction in a benzoic acid melt

Vitaly A. Demin ; Maxim I. Petukhov

Žurnal Sibirskogo federalʹnogo universiteta. Matematika i fizika, Tome 18 (2025) no. 1, pp. 100-108.

Résumé

The work is devoted to a numerical study of the transport of proton exchange reaction products in a benzoic acid melt after the interaction of its molecules with a lithium niobate crystal. Due to dissociative adsorption from the surface of the substrate, positive lithium ions and negative benzoate ions diffuse into the acid. The transfer of these reaction products is described using equations in the continuos media approximation. The mathematical model takes into account the diffusion and electromigration mechanisms of transport, as well as the recombination of ions. As a result of the solution, stationary distributions of ion concentrations are obtained. Due to the large difference in the kinetics of the reaction products, benzoate ions are grouped predominantly near the substrate, while lithium ions tend to move away from it to a much greater distance. The work shows that the size of the computational domain approaches the size of the reactor working space when the ions of both types form boundary layers.

Détail

Keywords: proton exchange, boundary layer, numerical simulation.

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