K-promoted Mo/Co- and Mo/Ni-catalyzed Fischer–Tropsch synthesis of aromatic hydrocarbons with and without a Cu water gas shift catalyst

Abstract

The catalyst systems Mo/Co/K/ZSM-5 and Mo/Ni/K/ZSM-5, alone and with the added copper-based water gas shift catalyst, were used for the conversion of two CO/H2 ratios in a batch reactor. GC analysis of the gas phase was used to determine CO conversion while GCMS and NMR studies were used to characterize the liquid products formed and liquid product selectivities. The liquids were hydrocarbons consisting mainly of alkyl substituted benzenes. Methyl substitution in the alkyl benzenes in the product liquid ranged from an average of 1.3 to 4.5 methyls per ring depending on reaction conditions and reactant gas mole ratios. The additional presence of the WGS catalyst significantly increased CO conversion in the reactions taking place at 280°C from ∼25% to ∼90% while increasing selectivity toward higher average methyl substitution. Similar conversions and selectivities were observed with both a bio-syngas and a 50/50 mixture of H2 and CO.