Abstract
Several reactor configurations have been tested for catalytic propane dehydrogenation employing Pt-Sn/MgAl2O4 as a catalyst. Pd-Ag alloy membranes coupled to the multifunctional Two-Zone Fluidized Bed Reactor (TZFBR) provide an improvement in propane conversion by hydrogen removal from the reaction bed through the inorganic membrane in addition to in situ catalyst regeneration. Twofold process intensification is thereby achieved when compared to the use of traditional fluidized bed reactors (FBR), where coke formation and thermodynamic equilibrium represent important process limitations. Experiments were carried out at 500–575 °C and with catalyst mass to molar flow of fed propane ratios between 15.1 and 35.2 g min mmol−1, employing three different reactor configurations: FBR, TZFBR and TZFBR + Membrane (TZFBR + MB). The results in the FBR showed catalyst deactivation, which was faster at high temperatures. In contrast, by employing the TZFBR with the optimum regenerative agent flow (diluted oxygen), the process activity was sustained throughout the time on stream. The TZFBR + MB showed promising results in catalytic propane dehydrogenation, displacing the reaction towards higher propylene production and giving the best results among the different reactor configurations studied. Furthermore, the results obtained in this study were better than those reported on conventional reactors.
Highlights
Nowadays, propylene is considered one of the most important basic products, especially in the plastics industry for polypropylene production
This multifunctional reactor provides in situ catalyst regeneration due to the Two-Zone Fluidized Bed Reactor (TZFBR) configuration, and a displacement of the main reaction towards propylene production by the selective removal of H2 in the “reaction zone”, i.e., molecular separation through the membrane
[Equations (2) and (3)] and coking [Equation (4)], which are favored at high temperatures. These results suggest that carrying out catalytic propane dehydrogenation in a traditional fluidized bed reactor is not efficient
Summary
Propylene is considered one of the most important basic products, especially in the plastics industry for polypropylene production. This multifunctional reactor provides in situ catalyst regeneration due to the TZFBR configuration, and a displacement of the main reaction towards propylene production by the selective removal of H2 in the “reaction zone”, i.e., molecular separation through the membrane. The multifunctional TZFBR + MB is employed to illustrate the improvement in the yield to propylene by displacement of the reaction equilibrium towards products resulting from the selective hydrogen removal This last study deals with the PDH system stability along the time on stream and the ability of counteracting the catalyst deactivation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
