| 초록 |
In the present study, we have prepared different modified iron based catalysts by different methods. Precipitated iron catalyst was prepared with magnesia, ceria, copper oxide as promoters by precipitation method using NH4(CO3)2, followed by drying and calcination at 300 oC for 2h. Mixture of iron-cobalt in different ratios, impregnated on silica gel support was prepared by incipient wetness impregnation method, followed by drying and calcining at 300 oC for 2 h. All calcined samples were impregnated with aqueous solution of potassium carbonate. The catalysts were characterized by different analytical techniques such as XRD, N2-physisorption, FTIR, TEM. From XRD, the presence of hematite (Fe2O3) phase was detected in the precipitated iron catalyst whereas all supported Co-Fe catalysts showed typical spinnel phase in their XRD spectra. The introduction of Fe, develops the bimodal pore size distribution in the silica supported samples around 40 Ǻ and 60 Ǻ. The performance of these catalysts have been studied for the Fischer-Tropsch synthesis (FTS) in a fixed bed reactor by varying reaction parameters. Co/SiO2 catalyst showed 85% CO conversion at 240 oC, 22 bar and H2/CO mole ratio 2 after 5h. |
