Averaging of the model of a chemical process in a catalyst layer with a spherical grain

The article presents a comparative analysis of models of a non-stationary chemical process using the example of burning coke sedimentation from a catalyst layer with a spherical grain. The first model is obtained by averaging the heat conductivity equation for a spherical catalyst grain. The second is the averaging of the entire grain model, including the diffusion-reaction equations. The comparative analysis showed good consistency of the results under conditions of low concentrations of reagents, small catalyst grains and high process temperatures with a significant reduction in calculation time for the first model. It was found necessary to take into account intradiffusion inhibition at the case of a high reagent concentrations. It causes the occurrence of a concentration gradient along the radius of the catalyst grain at the initial stages of the process.