Tunable synthesis of higher alcohols or formyl compounds (aldehydes and ketones) from syngas is attractive. However, precise control of the coordination between CO dissociative and CO non-dissociative sites, for inactive hydrogenation into aldehyde and ketone are still challenging. Herein, we realized a record-breaking oxygenate selectivity of similar to 70 wt% in organics at a mild temperature of 170 degrees C on the K-Fe catalysts, 88% of which is formyl compounds, ranking the highest among the related catalysts. A high selectivity of alcohols of 40.7 wt% is also observed on the Fe catalyst without modification. It is found that K promoter can adjust surface chemical environment (C-rich and H-lean surface) and reaction intermediates, furthermore, can prompt the CO non-dissociative sites from Fe2C to Fe for alcohol to formyl compound shift. This study provides an alternative strategy to adjust the interaction among active phases and impact on reactant activation to tune the different product distribution.
Key words
Syngas conversion/Aldehyde/Ketone/Potassium promoter/Iron catalyst/FISCHER-TROPSCH SYNTHESIS/TOTAL-ENERGY CALCULATIONS/ELASTIC BAND METHOD/CO HYDROGENATION/MIXED ALCOHOLS/CATALYSTS/IRON/CARBON/CONVERSION/STABILITY
NSTL
Elsevier