Acta Phys. -Chim. Sin. ›› 1996, Vol. 12 ›› Issue (05): 406-412.doi: 10.3866/PKU.WHXB19960505

• ARTICLE • Previous Articles     Next Articles

Catalytic Properties for Mixed Alcohols Synthesis and Structure of Co-K-Mo/γ-Al2O3

Bian Guo-Zhu,Ma Yun-Sheng,Fu Yi-Lu,Xie Ya-Ning,Hu Tian-Dou   

  1. Department of Chemical Physics,University of Science and Technology of China,Hefei 230026|Institute of High Energy Physics,Academia Sinica,Beijing 100039
  • Received:1995-09-22 Revised:1995-11-27 Published:1996-05-15
  • Contact: Fu Yi-Lu

Abstract:

A series of oxidic Co-K-Mo/γ-Al2O3 catalyst samples, prepared by impregnating oxidic K-MoO3/γ-Al2O3 samples with aqueous solution of calculated Co (NO3)2 and then calcination in air at temperatures of 350 ℃, 500℃, 650℃ and 800℃, respectively, were sulfided and then investigated for the synthesis of mixed alcohols from CO hydrogenation at conditions of p=5.0MPa, T=350 ℃ and GHSV=4800h-1. The results demonstrate that the addition of cobalt promoter is favourable to from higher alcohols and the samples calcined at 500-650 ℃ after impregnating Co2+ possess superior properties for the mixed alcohols synthesis.
The structures of Co and Mo species on the oxidic and sulfided samples were determined by XRD, LRS and EXAFS. For oxidic sample calcined at 350 ℃, cobalt exists as Co3O4 species and covers on the surface of K-Mo-O species, the structures of K-Mo-O species are same as that in K-MoO3/7-Al2O3 sample. After sulfidation, cobalt exists as sulfide crystallites with octahedral coordinated Co, and Mo... as MoS2 crystallites. For oxidic samples calcined at 500-650℃, Co component interacts with the K-Mo-O species and destroys the long-range order of the K-Mo-O species gradually. After sulfidation, Co tends to be existed as a sulfide with tetrahedral coordinated Co and Mo still as MoS2 crystallites. For oxidic sample calcined at 800℃, Co component exists mainly as Co(Al2O4) species, most of which can not be sulfided during sulfidation.

Key words: Co-K-Mo/γ-Al2O3 catalyst, Calcination temperature, Mixed alcohols synthesis, Structure