Steam reforming of methanol over a Cu/ZnO/Al2O3 catalyst: a kinetic analysis and strategies for suppression of CO formation
2002 (English)In: Journal of Power Sources, ISSN 0378-7753, Vol. 106, no 1-2, 249-257 p.Conference paper (Refereed)
Steam reforming of methanol (CH3OH + H2O --> CO2 + 3H(2)) was studied over a commercial Cu/ZnO/Al2O3 catalyst for production of hydrogen onboard proton exchange membrane (PEM) fuel cell vehicles. A simple power-law rate expression was fitted to experimental data in order to predict the rates Of CO2 and H-2 formation under various reaction conditions. The apparent activation energy (E-a) was estimated to be 100.9 kJ mol(-1), in good agreement with values reported in the literature. Appreciable amounts of CO by-product were formed in the reforming process at low contact times and high methanol conversions. Being a catalyst poison that deactivates the electrocatalyst at the fuel cell anode at concentrations exceeding a few ppm, special attention was paid to the pathways for CO formation and strategies for its suppression. It was found that increasing the steam-methanol ratio effectively decreases CO formation. Likewise, addition of oxygen or air to the steam-methanol mixture minimises the production of CO. By shortening the contact time and lowering the maximum temperature in the reactor, CO production can be further decreased by suppressing the reverse water-gas shift reaction.
Place, publisher, year, edition, pages
2002. Vol. 106, no 1-2, 249-257 p.
hydrogen production, methanol, steam reforming, Cu/ZnO/Al2O3 catalyst, carbon monoxide, PEM fuel cell vehicles, fuel-cell applications, copper-based catalysts, partial oxidation, hydrogen-production, cuznal(zr)-oxide catalysts, selective production, decomposition, mechanism, water
IdentifiersURN: urn:nbn:se:kth:diva-21512ISI: 000175342800036OAI: oai:DiVA.org:kth-21512DiVA: diva2:340210
QC 201005252010-08-102010-08-10Bibliographically approved