Tuning CO2 Hydrogenation to Light Olefin Selectivity via Cu/Zn/Zr Supported on Modified SAPO-34

Abstract

To alleviate CO₂ emissions and reduce reliance on fossil fuels, a groundbreaking bifunctional catalyst system was introduced, which ingeniously merged CZZ with modified SAPO-34 zeolite, to convert CO₂ into light olefins. Different metals were impregnated into SAPO-34 to form MeSAPO-34 (Me = Zn, Zr, Mn) and the metal Zr content was altered. Furthermore, CZZ and MeSAPO-34 was combined into CZZ/MeSAPO-34 composite catalysts, which was used for CO₂ hydrogenation. The MeSAPO-34 and xZrSAPO-34 catalysts were rigorously characterized by various techniques, revealing key physicochemical attributes. This innovative approach harnessed the synergistic effects between the metallic CZZ component and the modified zeolite to facilitate a series of reactions, effectively generating C₂-C₄-rich hydrocarbons. Benefiting from weak acid, higher oxygen vacancy concentration and interactions between components, the CZZ/ZrSAPO-34 catalyst system has shown remarkable efficiency in enhancing the light olefin selectivity. The key aspects of this system are its ability to modulate surface acidity and oxygen vacancy concentration, thus creating favorable conditions for light olefin production via enhanced tandem reaction based on CO₂ hydrogenation. This work enriches our insight into designing novel composite catalysts for promoting CO₂ conversion and hence mitigating CO₂ emissions.