Production of hydrogen via glycerol steam reforming in a Pd-Ag membrane reactor over Co-Al2O3 catalyst

摘要

Generally, biodiesel fuel, when converted from vegetables oils, produces around 10 wt% of glycerol as a byproduct, which could be used for producing hydrogen by a steam-reforming reaction. Different scientific works have been realized in conventional reactors on the steam reforming of glycerol (GSR) in the aqueous or the gas phase. High reaction pressure and a relatively small catalyst deactivation are noticed when GSR is carried out in an aqueous phase, whereas the catalyst deactivation is the main disadvantage in the gas phase. In this work, GSR reaction was performed in a perm-selective Pd-Ag membrane reactor (MR) packed with a Co-Al₂O₃ commercial catalyst in order to extract a CO-free hydrogen stream and also enhance the performances in terms of glycerol conversion and hydrogen yield with respect to a traditional reactor (TR), both working at weight hourly space velocity (WHSV) = 1.01 h−1, 400 °C and H₂O/C₃H₈O₃ = 6/1. In MR, a maximum glycerol conversion of around 45.0% was achieved at 1.0 bar as reaction pressure, whereas it was around 94% at 4.0 bar. Moreover, as best value, more than 60.0% of CO-free hydrogen recovery was achieved in the MR at 4.0 bar and 22.8 of sweep factor (sweep gas to glycerol ratio). Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.