Investigation on the promotional role of Ga2O3 on the CuO–ZnO/HZSM-5 catalyst for CO2 hydrogenation

Dimethyl ether (DME) can be directly synthesized from carbon dioxide and hydrogen by mixing methanol synthesis catalysts and methanol dehydration catalysts. The activity and selectivity of the catalyst can be greatly affected by the promoter; herein, we presented a series of CuO–ZnO–Ga₂O₃/HZSM-5 hybrid catalysts, which were prepared by the coprecipitation method. The effect of the Ga₂O₃ content on the structure and performance of the Ga-promoted Cu–ZnO/HZSM-5 based catalysts was thoroughly investigated. The results showed that the addition of Ga₂O₃ significantly increased specific surface areas and Cu areas, decreased the size of Cu particles, maintained the proportion of Cu⁺/Cu⁰ on the surface of the catalyst, and strengthened the metal–support interaction, resulting in high catalytic performance.

The additive Ga₂O₃ improved the catalytic performance of CuO–ZnO/HZSM-5 catalysts for hydrogenation of CO₂ to DME.