1Research Institute of Petroleum Industry (RIPI), P.O. Box 18745-4163 Tehran, I. R. IRAN
2Department of Chemical Engineering, University of Tehran, P.O. Box 11365-4563 Tehran, I. R. IRAN
3Department of Chemical Engineering, University of Tehran, P.O. Box 11365-4563 Tehran, I. R.
In a novel dual bed reactor Fischer-Tropsch synthesis was studied by using two diffrent cobalt catalysts. An alkali-promoted cobalt catalyst was used in the first bed of a fixed-bed reactor followed by a Rutenuim promoted cobalt catalyst in the second bed. The activity, product selectivity and accelerated deactivation of the system were assessed and compared with a conventional single bed reactor system. The methane selectivity in the dual-bed reactor was about 18.9 % less compared to that of the single-bed reactor. TheC5+selectivity for the dual-bed reactor was 10.9 % higher than that of the single-bed reactor. Accelerated deactivation of the catalysts in the dual-bed reactor was 42 % lower than that of the single-bed reactor. It was revealed that the amount of catalysts activity recovery after regeneration at 400 oC in the dual-bed system is higher than that of the single-bed system.
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