Pd-Ag Membrane Coupled to a Two-Zone Fluidized Bed Reactor (TZFBR) for Propane Dehydrogenation on a Pt-Sn/MgAl2O4 Catalyst

José-Antonio Medrano; Ignacio Julián; Javier Herguido; Miguel Menéndez

doi:10.3390/membranes3020069

Pd-Ag Membrane Coupled to a Two-Zone Fluidized Bed Reactor (TZFBR) for Propane Dehydrogenation on a Pt-Sn/MgAl2O4 Catalyst

Membranes (Basel). 2013 May 14;3(2):69-86. doi: 10.3390/membranes3020069.

Authors

José-Antonio Medrano¹, Ignacio Julián², Javier Herguido³, Miguel Menéndez⁴

Affiliations

¹ Catalysis, Molecular Separations and Reactor Engineering Group (CREG), Aragón Institute for Engineering Research (I3A), University of Zaragoza, Zaragoza 50018, Spain. 550765@unizar.es.
² Catalysis, Molecular Separations and Reactor Engineering Group (CREG), Aragón Institute for Engineering Research (I3A), University of Zaragoza, Zaragoza 50018, Spain. ijulian@unizar.es.
³ Catalysis, Molecular Separations and Reactor Engineering Group (CREG), Aragón Institute for Engineering Research (I3A), University of Zaragoza, Zaragoza 50018, Spain. jhergui@unizar.es.
⁴ Catalysis, Molecular Separations and Reactor Engineering Group (CREG), Aragón Institute for Engineering Research (I3A), University of Zaragoza, Zaragoza 50018, Spain. qtmiguel@unizar.es.

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.