Reaction Kinetics, Mechanisms and Catalysis

, Volume 128, Issue 1, pp 427–441 | Cite as

Exceptional catalytic performance of Au–Pt/γ-Al2O3 in naphtha reforming at very low Au dosing levels

  • Zahra Kianpoor
  • Cavus FalamakiEmail author
  • Mohammad Reza Parvizi


The catalytic behavior of Au–Pt bimetallic nanoparticles supported on γ-Al2O3 for the reforming reaction of a real desulfurized medium naphtha feed has been investigated. Composite catalysts containing 0.7 wt% metal(s) with Au/Pt weight ratios of 0:100, 1:99, 5:95, and 50:50 have been studied. XPS analysis showed that the ratio of 1:99 results in a distinct positive character of Pt in the Au–Pt nanoalloy. We show for the first time that through colorimetric analysis that the catalyst synthesized with the Au/Pt ratio of 1:99 exhibits clear surface plasmon resonance effects under visible light at 570 nm, peculiar to the electronic configuration supported by the XPS analysis. Naphtha reforming catalytic tests were performed in a WHSV range of 2–6 h−1, at 485 °C. The pressure was 5 bar, typical for continuous catalytic reforming processes. The Au/Pt ratio of 1:99 resulted in a distinct performance, i.e. maximum naphthenes conversion, maximum aromatics production and least production of benzene and hydrocarbons with a carbon number equal or less than 5. This was attributed to the formation of near-surface Au–Pt alloy with an Au mono-sublayer in the presence of H2 during the reaction. The optimal catalyst exceptionally favors dehydrogenation/dehydrogenation over hydrogenolysis reactions.


Naphtha reforming Au–Pt bimetallic γ-Al2O3 Surface plasmon resonance 



This work was partially financially backed by the Bouali Sina Petrochemical Co., Mahshahr, Iran, under the Contract No. BS/2-137.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Chemical Engineering DepartmentAmirkabir University of TechnologyMahshahrIran
  2. 2.Chemical Engineering DepartmentAmirkabir University of TechnologyTehranIran
  3. 3.Petrochemical Center of ExcellenceAmirkabir University of TechnologyTehranIran
  4. 4.Bouali Sina Petrochemical Co.MahshahrIran

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