Effect of the Type of the Cobalt-Containing Component of a Composite Catalyst on the One-Stage Synthesis of Liquid Hydrocarbons from СО and Н2

Abstract The effect of the type of the cobalt-containing component (Со-Al2O3/SiO2, Co-Re/Al2O3, and Co-Re/TiO2) of a composite catalyst on the combined synthesis and hydroconversion of hydrocarbons by the Fischer–Tropsch process are investigated. The catalytic properties of catalyst samples are studied in a flow reactor with a fixed catalyst layer at 2 MPa and GHSV of 1000 h–1 within a the temperature range of 240–280°С for 40–90 h of continuous operation. The highest values of output and selectivity to C5+ hydrocarbons are obtained for composite catalyst Со-Al2O3/SiO2(35%)/ZSM-5(30%)/Al2O3(30%) at a temperature of 240°C and are 106 kg/($${\text{m}}_{{{\text{cat}}}}^{3}$$ h) and 67.1%, respectively. It is shown that using Co-Re/Al2O3 instead of Со-Al2O3/SiO2 catalyst produces comparable values of catalytic activity, but considerably fewer unsaturated hydrocarbons are found in the products of synthesis. Using Co-Re/TiO2 catalyst and raising the temperature (to 280°С) shifts the molecular weight distribution of the products of synthesis toward the formation of a gasoline fraction. It is found that the rate of catalyst deactivation grows in the order Со-Al2O3/SiO2 > Co-Re/Al2O3 > Co-Re/TiO2.