The effect of multiple oxidation-reduction cycles on the catalyst performance was studied. Pt-Sn-Sn, Pt-Sn-Ir, Pt-Sn-Au and Pt-Sn-Pd supported on γ-Al2O3 were compared with the reference Pt-Sn/γ-Al2O3 catalyst in n-octane test reactions. The carbonaceous deposits were burned off from the catalysts after each reaction. The regeneration procedure consisted only two steps: the burn off in air and the reduction in hydrogen. No significant change, as a consequence of the regeneration, was observed in the conversion, the liquid yield and the product distribution, except at the Pt-Sn-Pd and Pt-Sn-Au catalysts. These catalysts lost part of their activity. With the palladium modified catalyst the rupture reactions became more dominant with the number of regeneration cycles. The aromatic part of the product decreased, the isoparaffin part increased in the case of both modified catalysts. The reference, the tin and iridium modified catalysts had stable catalytic performance: the activity and selectivity of the catalysts remained constant after a few oxidation cycles.
- Reforming catalyst (multimetallic)
ASJC Scopus subject areas
- Physical and Theoretical Chemistry