(307e) Pervaporation Membrane Reactors for Reversible Reactions: Modeling of the Membrane-Reactor Performance to System Design and Operating Conditions

Reversible organic reactions have enjoyed numerous laboratory uses and industrial applications since they are convenient means to prepare esters and ketals. Frequently, these reactions do not proceed to completion due to the thermodynamic limitations. Water or methanol is the typical by-product from these reactions. Selective removal of these by-products can shift the equilibrium towards higher conversions or yields. Conventional separation techniques, such as distillation and molecular sieves, have drawbacks in terms of efficiency as well as reactor design. Besides, these processes are not feasible for labile products and may bring about new waste by-products. Compared to traditional methods, selective removal of by-product through pervaporation membrane in a membrane reactor can save cost, increase reaction rate and is more energy efficient.

In this study, a pervaporation membrane reactor system is developed employing commercially available perfluorinated membranes manufactured by Compact Membrane Systems. This presentation will discuss the performance of the membrane for model reversible reactions. Our results indicate that the membrane reactor system can rapidly achieve higher conversion than that achieved in the conventional system. The membrane has a high permselectivity of by-products over reactants. Moreover, a prediction model is developed to predict membrane reactor performance based on membrane permeation data (specie permeate through membrane) and operation conditions (reactor temperature, permeate pressure and feed composition). The model is validated using available experimental data and a good agreement is found. Effects of membrane selectivities and permeate pressure on membrane reactor performance for two model reactions are investigated by the developed model. This model can also be used for the other organic reversible reactions with water or low molecular weight alcohol by-products liberated.