Victor Baldovino-Medrano - The functionalities of Pt/γ-Al2O3 catalysts in simultaneous HDS and HDA reactions

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      Publication Details (including relevant citation   information):

      Fuel Volume 87, Issues 10–11, August 2008, Pages 1917–1926

      Abstract:

        A Pt/γ-Al2O3    catalyst was tested in simultaneous hydrodesulfurization (HDS) of   dibenzothiophene and hydrodearomatization (HDA) of naphthalene   reactions. Samples of it were subjected to different   pretreatments: reduction, reduction–sulfidation, sulfidation with   pure H2S   and non-activation. The reduced catalyst presented the best   performance, even comparable to that of Co(Ni)Mo catalysts. All   catalyst samples were selective to the HDS reaction over HDA, and   to the direct desulfurization pathway of dibenzothiophene HDS   over the hydrogenation reaction pathway of HDS. The effect of   H2S   partial pressure on the functionalities of the reduced   Pt/γ-Al2O3    catalyst was studied. The results showed that an increase in   H2S   partial pressure does not cause poisoning, but an inhibition   effect, without changing the catalyst selectivity. Accordingly,   the activity trends were ascribed to adsorption differences   between the different reactive molecules over the same catalytic   active site. TPR characterization along with a thermodynamics   analysis showed that the active phase of reduced   Pt/γ-Al2O3    is constituted by Pt0    particles. However, presulfidation of the catalyst leads to a   mixture of PtS and Pt0    which has a negative effect on the catalytic performance without   changing catalyst functionalities.

      Address (URL): http://www.sciencedirect.com/science/article/pii/S001623610700539X