The Influence of the Cobalt-Containing Component of the Composite Catalyst on the One-Stage Process for Synthesis of Liquid Hydrocarbons from CO and H2

The influence of the cobalt-containing component (Co-Al2O3/SiO2, Co-Re/Al2O3 and Co-Re/TiO2) of a composite catalyst was studied in the Fischer – Tropsch combined process for synthesis and hydrotransformation of hydrocarbons. A flow fixed-bed reactor was used for characterization of the catalytic properties at 2 MPa, flow rate 1000 h–1, 240–280 °C for 40–90 hours of continuous operation. The highest productivity and selectivity to C5+ hydrocarbons equal to 106 kg/(m3 cat·ч) and 67.1 %, respectively, was characteristic of the composite catalyst Co-Al2O3/SiO2(35%)/ZSM-5(30%)/Al2O3(30%) at 240 °C. The comparable activities were observed with the catalysts Co-Re/Al2O3 and Co-Al2O3/SiO2 but the former provided the formation of unsaturated hydrocarbons in a lower proportion in the products. The use of the Co-Re/TiO2 catalyst at elevated temperature (up to 280 °C) allowed the molecular mass distribution of the products to be shifted towards the formation of the gasoline fraction. The rate of the catalyst deactivation was established to increase in the series Co-Al2O3/SiO2 > Co-Re/Al2O3 > Co-Re/TiO2.