A model of an airlift reactor in the cases of interphase mass transfer between gas and liquid in the riser and chemical reaction in the liquid phase has been done. The model equations permit to obtain the vertical distribution of the average concentrations of an active gas component in gas and liquid phases and average concentration of the active liquid component, using average velocities and effective diffusivities in the riser and downcomer zones. The proposed model allows scale-up problem solution. An hierarchical approach for model parameter identification on the bases of experimental data has been proposed. (c) 2006 Elsevier Ltd. All rights reserved.