Synthesis, characterization, and catalytic performance of NiMo catalysts supported on different crystal alumina materials in the hydrodesulfurization of diesel

Abstract A series of alumina with different crystal structures from γ-Al 2 O 3 to θ-Al 2 O 3 has been synthesized by precipitation method using aluminum nitrate and aluminum chloride hexahydrate, and the corresponding NiMo/Al 2 O 3 catalysts were prepared based on above different alumina. The typical physic-chemical properties of the supports and series catalysts were characterized with XRD, BET, UV–Vis DRS, Py-IR, Raman and XPS characterization methods, and their catalytic activities were tested for FCC diesel hydrodesulfurization. The catalytic system was tested in hydrodesulfurization reactions of FCC diesel under atmospheric and high pressure (5 MPa). The NiMo/δ-Al 2 O 3 catalyst prepared by aluminum nitrate exhibited the highest HDS and HDN efficiencies, 99.4% and 99.3% respectively, which were mainly ascribed to the concentrated pore size distribution, moderate MSI and higher degree of sulfidation.