Comparing the performance of Co/CNT and Co,Ru/CNT nano catalysts using microemulsion technique in Fischer- Tropsch synthesis

Cobalt and Bimetallic cobalt-ruthenium nano catalysts supported on carbon nanotubes (CNTs) are prepared using microemulsion technique with water to-surfactant ratios of 0.5−1.5. The nano catalysts were extensively characterized by different methods and their activity and selectivity in Fischer-Tropsch synthesis (FTS) have been assessed in a fixed-bed microreactor. The physicochemical properties and performance of the 15 wt% Co, 1 wt% Ru/CNT nanocatalysts were compared with the 15wt% Co/CNT nanocatalysts. the use of microemulsion technique with water to surfactant ratio of 0.5 decreased the average cobalt oxide particle size to 4.8-4.9 nm, the dispersion was almost doubled and the reduction increased . Ruthenium was found to enhance the reducibility of Co3O4 to CoO and that of CoO to Co0, increase the dispersion and decrease the average cobalt cluster size. Moreover 1 wt% Ru increased the FTS rate of 15 wt.%Co/CNT catalyst from 0.362 to 0.372 gHC/(gcat.h) and enhanced the selectivity of FTS towards the higher molecular weight hydrocarbons

Keywords:

Fischer-Tropsch synthesis , cobalt , ruthenium , microemulsion