Modeling study of a pervaporation membrane reactor for improving oxime hydrolysis reaction

The conversion of equilibrium-limited reactions can be efficiently improved by selective removal of product using a Pervaporation Membrane Reactor (PVMR), which attracts substantial attentions due to its excellent performance. For modeling the PVMR process, a pseudo-binary system was often assumed, nevertheless, it is inadequate to predict the performance when both the reactant and product have the similar properties and can simultaneous permeate through the membrane. A detailed model was established by coupling multi-component pervaporation and reaction kinetics with the butanoxime hydrolysis reaction employed as the experiment system. A modified Flory–Huggins (FH) approach and the Maxwell–Stefan (MS) formulation were used to describe the pervaporation model. The mass transfer fluxes and the concentration profiles of permeants within the membrane were modeled by a finite difference approach. Two coexisted behaviors, i.e. competitive adsorption and plasticizing effects were considered to influence mass transfer. The PVMR performance was predicted and a good agreement between experiment and calculation was obtained. The mechanism that how the simultaneous permeation of reactant and product influence the PVMR performance were further clarified in different operating conditions, including initial reactant concentration, downstream pressure, membrane thickness, ratio of membrane area to reaction volume, and temperature.