Conversion of CO2 to higher alcohols on K-CuZnAl/Zr-CuFe composite

Direct conversion of CO2 into higher alcohols (C2+OH) is highly desirable, but rather challenging due to requiring the synergetic action of C-C coupling and CO insertion. Here, we developed a new K-CuZnAl/Zr-CuFe composite, which gave CO2 conversion and C2+OH selectivity of 40.6% and 22.4% respectively, while CO selectivity is only 10.3% at 320 °C, 4 MPa and 6000 mL gcat−1 h−1. The C2+OH STY can reach 195.1 mg gcat–1 h–1, and is well maintained within 200 h at higher GHSV of 24000 mL gcat−1 h−1. Introduction of K-CuZnAl and decrease of the contact distance of K-CuZnAl and Zr-CuFe boost the formation and subsequent conversion of CO* intermediate. In addition, doping small amounts of Zr into CuFe catalyst hinders the phase separation of Cu and Fe species by enhancing their interface interaction. As a result, the CHx * species generated on iron carbide through CO* dissociative activation quickly reacts with the non-dissociative adsorbed CO* on adjacent Cu to produce more C2+OH.