Promotion of CO/SiO2 Fischer-Tropsch catalysts with zirconium

The effect of zirconia addition at various loading ratios on the performance Of 10 wt% Co/SiO2 catalysts for the so-called reaction of Fischer-Tropsch synthesis has been studied. The catalysts were prepared through a new pesudo sol-gel method which permits an uniform distribution of the incorporated components and a low deviation from theoretical composition. By increasing zirconia, Co-SiO2 interaction decreases and is replaced by Co-Zr interaction which favours reduction of the catalysts at lower temperatures. The activity and selectivity toward higher hydrocarbons of the promoted catalysts increase with increasing zirconium loading ratios. No appreciable decrease in activity was observed when all catalysts were employed under H-2/CO = 2 at 230 degreesC and 8 bar for 240 h. (C) 2002 Elsevier Science B.V. All rights reserved.