Kinetic analysis via mathematical modeling for ferrous iron oxidation in a class of SBR-type system

This paper analyses the oxidation of ferrous iron via chemical and biological means in a class of Sequential Batch Reactors (SBR-type). For this, a kinetic model for the study of iron oxidation system is proposed, followed by a parametric sensitivity analysis and a bifurcation analysis, which allow selecting the most influential kinetic parameters in order to ensure a suitable prediction capacity of the mathematical structure. The system consists of two SBR bioreactors, the first being used to produce hydrogen peroxide (H₂O₂) that is fed to a second reactor where the iron oxidation is carried out by chemical–biological processes. Model predictions were compared with experimental data for the production of H₂O₂ and for ferrous iron oxidation, finding suitable correlation coefficients (r² > 0.98) for each state variable. The bifurcation analysis showed the trajectories of the main variables, such as, biomass, H₂O₂ and ferrous iron, under the change of the most influential kinetic parameters. This analysis demonstrates the usefulness of the constructed model to predict the kinetic behaviour of the SBR-type process.