Zn promoted GaZrO_x Ternary Solid Solution Oxide Combined with SAPO-34 Effectively Converts CO₂ to Light Olefins with...

We proposed a new strategy for CO₂ hydrogenation to prepare light olefins by introducing Zn into GaZrO_x to construct ZnGaZrO_x ternary oxides, which was combined with SAPO-34 to prepare a high-performance ZnGaZrO_x/SAPO-34 tandem catalyst for CO₂ hydrogenation to light olefins. By optimizing the Zn doping content, the ratio and mode of the two-phase composite, and the process conditions, the 3.5 %ZnGaZrO_x/SAPO-34 tandem catalyst showed excellent catalytic performance and good high-temperature inhibition of the reverse water-gas shift (RWGS) reaction. The catalyst achieved 26.6 % CO₂ conversion, 82.1 % C₂ ⁼-C₄ ⁼ selectivity and 11.8 % light olefins yield. The ZnGaZrO_x formed by introducing an appropriate amount of Zn into GaZrO_x significantly enhanced the spillover H₂ effect and also induced the generation of abundant oxygen vacancies to effectively promote the activation of CO₂. Importantly, the RWGS reaction was also significantly suppressed at high temperatures, with the CO selectivity being only 46.1 % at 390 °C.