Fischer-Tropsch Synthesis in a Fixed Bed Tubular Reactor using Cobalt and Iron Catalysts

Fischer-Tropsch (FT) synthesis performance of cobalt and promoted iron catalyst prepared by incipient wetness impregnation method was investigated in a fixed bed tubular reactor at 7 bar and three different temperatures (493 K, 523 K and 563 K). Syngas with a composition of CO:H2 (1:2) was used for FT studies. Liquid products and tail gases were analyzed by gas chromatography. Alpha value for each run was measured and it was found that it decreases with increase in temperature. Selectivity of both catalysts was measured and it was observed that the probability of chain growth decreases with increase in temperature. The 493 K was found to be good operating temperature for cobalt catalyst to give high selectivity of diesel range. For iron catalyst gasoline production is more favoured at 563 K and presence of carbon dioxide in tail gases showed that water gas shift (WGS) reaction is favoured at high FT temperatures. Also methane selectivity was more pronounced at 563K for both catalysts. For the given temperature range, it was observed that promoted iron catalyst was less influenced by the reaction temperature as compared to unpromoted cobalt catalyst.&nbsp