Highly Active Catalytic CO 2 Hydrogenation to Lower Olefins via Spinel ZnGaO x Combined with SAPO-34

A key primary method for creating a carbon cycle and carbon neutrality is the catalytic hydrogenation of CO into high value-added chemicals or fuels. In this work, ZnGaO oxides were prepared by parallel co-precipitation and physically mixed with SAPO-34 molecular sieves prepared by hydrothermal synthesis to produce ZnGaO /SAPO-34 bifunctional catalysts, which were evaluated for the catalytic synthesis of lower olefins (C -C ) from carbon dioxide hydrogenation. It was demonstrated that the reaction process requires oxygen defect activation, synergistic hydrogenation, and CO alkaline adsorption of ZnGaO . The spinel structure of ZnGaO has more abundant oxygen defects and alkaline adsorption sites than the ZnGaO solid solution, which effectively enhances the catalytic performance. The CO conversion was 28.52%, the selectivity of C -C in hydrocarbons reached 70.01%, and the single-pass yield of C -C was 10.95% at 370 °C, 3.0 MPa, and 4800 mL/g /h.