Zone-coated Rh-based monolithic catalyst for autothermal reforming of diesel
2011 (English)In: Applied Catalysis B: Environmental, ISSN 0926-3373, E-ISSN 1873-3883, Vol. 101, no 3-4, 226-238 p.Article in journal (Refereed) Published
In this work we present results of hydrogen generation from diesel via autothermal reforming (AIR) obtained with monolithic catalysts consisting of either one or two layers of monometallic Rh and bimetallic RhPt washcoats. The Rh metal loading of the monometallic washcoats was varied between 0.5, 1.0 and 3.0 wt%, while the weight ratio of Rh:Pt in the bimetallic washcoats was kept constant at 1:1. Furthermore, non-doped and CeLa-doped catalysts were also tested to detect differences in catalyst activity. The catalysts consisting of two layers of washcoats were termed zoned catalysts and each layer was applied to some given length in the axial direction of the monolith. All catalysts were prepared by impregnation using the incipient wetness technique with delta-Al2O3 B as support and deposited onto 400 cpsi cordierite monoliths. A total of eight catalysts, including both single layered and zone-coated, were tested in a bench-scale reactor using low-sulfur diesel as fuel at operating conditions H2O/C=2.5, O-2/C=0.49 (lambda = 0.33), GHSV 17,000 h(-1) and P = 1 atm. The results showed that the zoned catalyst, covered with the two washcoats Rh1.0Pt1.0-Ce10La5.0/delta-Al2O3 and Rh-3.0-Ce10La10/delta-Al2O3, respectively, was most active in terms of fuel conversion and hydrogen production. The zoned catalyst's long-term performance and stability was also evaluated in a full-scale reactor using low-sulfur and Fischer-Tropsch diesels at operating conditions H2O/C = 2.5, O-2/C = 0.49 (lambda =0.33), GHSV= 10,800 h(-1), P = 1 atm, and at H2O/C = 2.4, 02/C = 0.39 (lambda=0.26), GHSV- 10,200 h(-1), P = 1 atm. respectively. The results showed that high fuel conversion and hydrogen production were obtained from both fuels. In addition, partial oxidation and steam reforming reactions were identified by closely studying the distribution of the analyzed product gas composition and the temperature measurements. Fresh and aged samples of the catalysts were characterized by N-2-BET, H-2 chemisorption, XRD, H-2-TPR, O-2-TPO and XPS analyses.
Place, publisher, year, edition, pages
2011. Vol. 101, no 3-4, 226-238 p.
Autothermal reforming, Diesel, Rhodium, Zone-coated monolithic catalyst
IdentifiersURN: urn:nbn:se:kth:diva-31649DOI: 10.1016/j.apcatb.2010.09.027ISI: 000287068400009ScopusID: 2-s2.0-78650307598OAI: oai:DiVA.org:kth-31649DiVA: diva2:405107
QC 201103212011-03-212011-03-212011-04-18Bibliographically approved