Propane Dehydrogenation Reaction in a High-Pressure Zeolite Membrane Reactor

In this work, a silicalite membrane reactor was used for the propane dehydrogenation (PDH) reaction for different operating conditions such as 550-650 °C for temperature and 1-5 atm for pressure, respectively. Packed bed membrane reactors (PBMRs) were allowed to achieve higher performance than packed bed reactors, thereby overcoming thermodynamic limitations that are prevalent in dehydrogenation reactions. Removal of one of the reaction products (H2) during the reaction from the reaction side helped in improving PDH reaction performance of PBMR. Pt/Al2O3 catalysts were used with the silicalite membrane to explore the impact of operating conditions on the PDH reaction. Increasing reaction temperature accelerated the reaction rate, which led to an increase in propane conversion. Increasing reaction pressure led to an increase in H2 permeation across the membrane, which resulted in considerable improvement in the propane conversion. The highest propane conversion, propylene selectivity, and propylene yield achieved were 49, 97, and 47%, respectively, at 600 °C and 5 atm in the PBMR mode. The selective removal of H2 from the reaction side through the membrane was also found to significantly reduce the side products such as methane. A one-dimensional plug flow model was developed and found to work well for simulating the PDH reaction.