The catalytic oxidation of H2S in a stainless steel membrane reactor with separate feed of reactants.

The oxidation of H2S is studied in a membrane reactor with separate feed of reactants. As a novelty in the concept of separate introduction of the reactants, a sintered stainless steel membrane is used, because this type of material is easy to integrate into the reactor, and the catalytic properties of the membrane itself makes the often difficult activation superfluous. The macropore membrane (dp>1 μm) is characterized in the absence of a pressure difference by diffusion and conversion experiments for determining the porosity to tortuosity ratio. Because the relative large pore diameter of the membrane, Knudsen diffusion is of minor importance and the last important structure parameter of the membrane, B0, is determined in a permeation experiment. This membrane reactor is also studied in the presence of a pressure difference over the membrane; a situation where both diffusion and convection affect the overall mass transfer. For this reason, a model based on the dusty gas model (DGM) is used, where the structure parameters are estimated from isobaric conversion and permeation measurements and the physical constants are taken from literature. This model predicts the conversion in the presence of a pressure difference very well, without using fit parameters. Generally, it can be concluded that the performance of this sintered metal membrane reactor can be described and operated equally compared to ceramic membrane reactors with separate feed of reactants. Regarding the fact that there are several other types of sintered metals (e.g. nickel, silver or platinum), this type of membrane reactor seems to be applicable for several other chemical applications.