The coprecipitation of sodium silicate with cobalt nitrate, combined with an n-butanol drying process, led to the formation of a Co-O-Si complex oxide (Co/Si atomic ratio approximate to 0.65) with atomically dispersed Co and Si atoms. The complex oxide had a high surface area (562 m(2)/g) and strong surface acidity. Sulfidation resulted in the formation of highly dispersed cobalt sulfide, which had high activity in the hydrodesulfurization (HDS) of thiophene (99.4%) and skeletal isomerization of 1-hexene (35%) at 573 K The HDS activity was as high as that of the industrial catalyst Co-Mo/gamma-Al2O3, although no Mo was present. The material could therefore be used for the skeletal isomerization of linear olefins during deep HDS of gasoline to reduce octane number loss caused by olefin saturation. (C) 2014, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.