Title : Syngas conversion into higher alcohols over KCoMoS2–catalysts supported on graphene-nanosheets coating alumina and carbon-containing materials
Catalytic conversion of synthesis gas to higher alcohols has received tremendous interest due to the generation of environmentally benign octane boosters and alternative fuels to supplement the diminishing supply of the world’s finite fossil fuel reserves. K–modified CoMoS2 catalysts supported over carbon-containing materials such as γ-Al2O3, Carbon-Coated Alumina (CCA), Graphene coated Alumina (GCA), and different types of powdered and fiber commercial activated carbons were prepared and characterized by BET, XRF, SEM, SEM-EDX, and HRTEM. Supporting efficiency of γ-Al2O3 to synthesis alcohols from syngas via KCoMoS2 catalyst improves after being coated with amorphous carbon and graphene because the carbon materials played a role in decreasing the interaction between alumina and active phase besides it has decreased the hydrogenation reaction. Powdered and fiber commercial activated carbons have shown different activities to increase the yield and selectivity of alcohol products. The catalytic activity increased in the order TCA < OBC-1< DAC < AHM < AG-3 < BAW. It was found that catalysts supported on microporous materials possessed higher catalytic activity in HAS synthesis from syngas than mesoporous materials. We explained this phenomenon by the distribution of the active phase inside the pores and the catalyst acidity. These results give deeper insight into the catalyst design of supported-TMS for HAS.