Sulfidability and thiophene hydrodesulfurization activity of supported NiMo carbides

Ni-Mo carbides supported on activated carbon were synthesized by carbothermal hydrogen reduction and the effect of the sulfidability on the thiophene hydrodesulfurization catalytic activity was studied. The X-ray diffraction patterns of Ni-Mo carbides showed the presence of β-Mo ₂C and NiC when the atomic ratio AR = Ni/(Ni + Mo) was between 0.25 and 0.75, while for AR = 1, it only was detected metallic Ni. The X-ray photoelectron spectroscopy results showed the distribution of different surface species in the passivated catalysts: Mo^{δ +} (0 ≥ δ ≤ 2), Mo^{4 +}, Mo^{6 +}, Ni^{δ +} and Ni ^{2 +}. After sulfiding the carbides were modified in their surface and catalytic activity.