Direct hydrogenation of CO2 to higher alcohols is highly attractive and challenging. Iron catalysts are generally not regarded as ideal candidates, owing to its poor ability for non-dissociative CO activation, and needs to combine with other metals (such as Rh, Pd, Cu) for above process. Herein, we proposed an iron catalyst co-modified with Na and S (FeNaS-0.6), achieving a space-time yield of 80.5 mg gcat−1 h−1 for alcohols, more than 98 % of which corresponds to C2+ alcohols. The synergistic effects of Na and S enable the monometallic iron catalyst to provide matched molecularly adsorbed CO and alkyl species simultaneously required for higher alcohols synthesis. Sulfur existed in the form of sulfate, and its electron-withdrawing effects could transfrom the surrounding Fe sites for CO dissociation to those for non-dissociative CO adsorption. The DFT modeling also confirmed more facile formation of alcohols on the Na and S co-modified iron catalyst.
ASJC Scopus subject areas
- Environmental Science(all)
- Process Chemistry and Technology