Conversion of syngas to hydrocarbons using bifunctional cobalt catalysts containing HZSM-5 zeolites of various porous structures

New bifunctional composite catalysts for the Fischer—Tropsch synthesis were developed on the basis of a mixture of the Co—Al2O3/SiO2 catalyst, meso-HZSM-5 hierarchical mesoporous zeolite, and boehmite binder. The mesoporous zeolite was obtained by alkaline treatment of the industrial HZSM-5 zeolite. The developed catalysts are suitable for one-pot conversion of syngas into linear C5+ hydrocarbons, which then undergo cracking and isomerization reactions. The effect of the concentration of NaOH solution on the porosity and catalytic efficiency of the obtained meso-HZSM-5 zeolite was studied. The performances of the bifunctional catalysts obtained from alkali-treated and pristine HZSM-5 in the conversion of syngas were compared. In the presence of the catalyst based on the alkali-treated zeolite, the total productivity to C5+ hydrocarbons somewhat decreases. However, the increase in the total yield of branched and unsaturated hydrocarbons provides the formation of motor fuels with high anti-knock properties.