Enhancement of Cobalt Catalyst performance and Stability in Fischer-Tropsch Synthesis Using Graphene Nanosheets as Catalyst Support

Graphene nano sheets (GNS) supported cobalt catalyst, is introduced for Fischer-Tropsch synthesis (FTS). The catalyst was prepared using wet impregnation method with cobalt loading of 15.0 wt%. The physico-chemical properties of the catalyst is investigated by TPR, TPD, BET, XRD, TEM and H2 chemisorption methods. The performance of the catalyst was assessed in a fixed bed micro-reactor at 220oC, 18 bars and H2/CO ratio of 2. The results were compared with those of Co/ γ-alumina. Using GNS as cobalt catalyst support decreased the average cobalt particles size from 16 to 9 nm, increased cobalt dispersion from 6 to 21% and improved the catalyst reducibility by a factor of 2.25. The activity of Co/GNS catalyst in FTS enhanced in comparison with that obtained for Co/γ-Al2O3. The products selectivity showed a slight shift to lower molecular weight hydrocarbons. Using GNS as catalyst support increased the catalyst lifetime.