Geovana S. V. Martins, Everton R. F. dos Santos, Meiry G. F. Rodrigues, Gina Pecchi, Carlos M. N. Yoshioka, Dilson Cardoso
Chemical Engineering Department, Federal University of Campina Grande.
Chemical Engineering Department, Federal University of Campina Grande, Catalysis Laboratory (LABNOV), Campina Grande, Brazil.
Chemical Engineering Department, Federal University of S?o Carlos, Catalysis Laboratory (LabCat), S?o Carlos, Brazil.
Facultad de Ciencias Químicas, UniversidadConcepción, Concepción, Chile.
DOI: 10.4236/mrc.2013.24017   PDF    HTML     5,524 Downloads   10,834 Views   Citations

Abstract

The aim of this work was to evaluate the catalytic properties for n-hexane isomerization of bifunctional monometallic (Ni or Pt) and bimetallic catalysts (Pt-Ni), using HMOR zeolite as support. The method used for metal dispersion in the zeolite was competitive ion exchange using ammine complexes [Ni(NH₃)₆]Cl₂ and [Pt(NH₃)₄]Cl₂ as precursors. The catalysts were characterized by X-Ray diffraction, X-Ray energy dispersion spectroscopy, temperature-programmed reduction and transmission electron microscopy. The n-hexane isomerization reaction using the catalysts was carried out to evaluate the catalyst activity. The reaction was carried out in a fixed bed reactor operating at 250?C, 1 atm, H₂/C₆ = 9 molar ratio. The profiles obtained from TPR suggest that, for bimetallic catalysts, the presence of platinum facilitates the reduction of Ni²⁺ cations. The bimetallic catalysts presented a higher activity in the isomerization of n-hexane when compared to the monometallic ones, as well better stability as the Pt content in the solid increases.

Keywords

N-Hexane; Isomerization; Mordenite; Nickel; Platinum

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Conflicts of Interest

The authors declare no conflicts of interest.

References

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