Modeling of a gas–liquid reactor in batch conditions. Study of the intermediate regime when part of the reaction occurs within the film and part within the bulk

Abstract A model is proposed for irreversible gas–liquid reactions, especially in the so-called ‘intermediate regime’ where the liquid phase mass transfer coefficient and the chemical reaction rate lead to a situation where part of the reaction occurs within the bulk and part occurs within the film. Firstly, the film theory is used but a new parameter, the depletion factor, is introduced in addition to the usual enhancement factor. A second part of the model includes the mass balances within a gas–liquid reactor and allows the overall behavior of the reactor to be described over time, by calculating the Hatta number, the enhancement factor and the depletion factor at any time. This method, using matlab software, allows the determination of that part of the reaction occurring within the liquid film and that occurring within the bulk liquid. The model is validated by a set of experiments on fumaric acid ozonation in a semi-batch reactor.