1 research outputs found
Hydrodesulfurization of 4,6-Dimethyldibenzothiophene over CoMo Catalysts Supported on γ‑Alumina with Different Morphology
Nanostructured γ-alumina with
two different morphologies (rod-like and cube-like) was used as support
for CoMo hydrodesulfurization catalyst. Both γ-aluminas were
prepared by thermal decomposition of ammonium aluminum carbonate hydroxide
precursor, which was synthesized by a convenient hydrothermal method
at two pH values. Fourier transform infrared spectroscopy of prydine
adsorption, thermogravimetric analysis, and <sup>27</sup>Al magic
angle spinning (MAS) NMR showed that the rod-like γ-alumina
exhibited a lower acidity than the cube-like γ-alumina. The
result of X-ray diffraction and temperature-programmed reduction indicated
that CoMo oxidic catalysts supported on the rod-like γ-alumina
presented higher reducibility compared to those of cube-like γ-alumina,
because more β-CoMoO<sub>4</sub> was formed on the surface of
the rod-like γ-alumina than that of the cube-like γ-alumina.
After sulfidation, a large stack with slightly longer MoS<sub>2</sub> slabs was formed on the rod-like γ-alumina supports, thereby
creating a catalyst with higher hydrodesulfurization activity and
hydrogenation selectivity. The morphology of γ-alumina has an
influence on the activity and selectivity of the as-synthesized CoMo
catalyst