Elsevier, Journal of Catalysis, (321), p. 51-61
DOI: 10.1016/j.jcat.2014.11.001
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Novel 1D-γ-Al2O3 nanorods were used to prepare a NiW hydrodesulfurization catalyst. Acid/base measurements of the NiW/Al-catalyst revealed a mainly weak and lower acidity and a great quantity of Lewis sites in oxide/sulfided forms. HRTEM exposed a homogeneously distributed active phase all over the surface of the Al-nR supported catalyst. Marked differences on the stacking degree and slabs length were observed when compared both materials. The activity for NiW/Al-nR resulted higher than that obtained for NiWP/γ-Al2O3 catalyst. Even when both materials showed almost the same specific hydrogenation rate, the main change was the higher hydrogenolysis on the NiW/Al-nR catalyst. Theoretical calculations showed that 1T-S-W-S cluster with Ni on the top resulted with less metallic character than when Ni was modeled in a corner of a 2H-S-W-S 3D crystal. For that reason, it was proposed that Ni-W-S sites on small slabs could act rather as hydrogenolysis sites than as hydrogenation sites.