(100c) Synthesis of Higher Alcohols From Syngas Over a K Promoted Cu-Co-Zn Catalyst In Supercritical n-Hexane

Synthesis of higher alcohols, isobutanol in particular, from coal, biomass or natural gas via synthesis gas (syngas) has been attracting researchers' interests due to the potential for producing clean and high octane value fuels. Higher alcohols could be used directly as fuels, as fuels additives for octane or cetane enhancement,  and as feedstocks in the chemical industry. Due to the exothermic nature of the reactions and the kinetic restrictions, this procedure suffers from poor productivity and selectivity towards higher alcohols.  For the last two decades, there has been intensive research centered on shifting the synthesis away from methanol and toward higher alcohols, including; i. the use of modified catalysts, ii. utilizing dual-bed reactors, or iii. slurry phase reactors. In this study, a supercritical medium (i.e. hexane) was employed to investigate the supercritical solvent effect on the formation of higher alcohols. A Cu-Co based catalyst was prepared by a coprecipitation method and evaluated in a fixed bed reactor. The results of catalytic investigations with and without the supercritical hexane medium demonstrated that supercritical hexane has a significant effect on the syngas conversion and the productivity towards higher alcohols.