A cellular automata approach to chemical reactions : 1 reaction controlled systems

A direct link between the chemical reaction controlled (shrinking core) model and cellular automata, to study the dissolution of particles, is derived in this paper. Previous research on first and second order reactions is based on the concentration of the reactant. The present paper describes the reaction kinetics based on particles and takes into account the shape and specific surface of these particles. As a vehicle for the present study of cellular automata, a simplified version of the CEMHYD3D model is used. During the research it was found that during the dissolution of particles, additional reactive surface was created due to the dissolution of voxels in the middle of the top-surfaces. Therefore a modification of the dissolution routine within CEMHYD3D was introduced. This modification introduced the preference of the system to dissolve voxels on the outside of the particles rather than the middle of the top-surfaces of the particles. In this way the increase of reactive surface is prohibited and a spherical shape maintained. Using this modification, it is proven that the dissolution of digitized particle can be describe based on the chemical reaction controlled system. Based on 165 simulations a general linear relation between cycles and time was derived. The derived model can describe the reaction sufficient up to 99.9%. Therefore it can be concluded that the single ‘cellular automata’ particle unambiguously related to the chemical controlled reactions