Abstract: The SiO₂-TiO₂-ZrO₂ composite oxide was prepared by Sol-Gel method. The effects ofn(Si)/n(Ti)/n(Zr)on the specific surface area , pore structure, acidity and crystal structure of the composite oxide were examined, and the thermal stability of samples was also characterized .The samples were tested by XRD, nitrogen absorption and infrared spectroscopy of absorbed pyridine. The feasibility of the composite oxide as the support of hydrofining catalyst was investigated by using dibenzothiophene as a model compound through hydrodesulfurization (HDS) reactions. The results indicated that mesoporous particles of the composite oxide were obtained .Compared with single and binary composite oxide, the specific surface area, the thermal stability and crystal stability ofSiO₂-TiO₂-ZrO₂ composite oxide were obviously improved. When n(Si)/n(Ti)/n(Zr) is equal to 0.163/0.809/0.028 , the specific surface is 315.32 m²/g, pore volume is 0.33 cm³/g and the aperture is 12.0 nm. The dibenzothiophene sulfur removal rate for MoP/SiO₂-TiO₂-ZrO₂ is 99.6% and desulfurization of diesel samples is above 96% . And desulfurization activity of catalyst is stability after 1200 h running.

Key words: Sol- G el method, ternary composite oxide, carrier, hydrodesulfurization