Preparation of Ga-intercalated modified CuZnAlGa-based hydrotalcite-derived catalysts and methods for improving CO conversion in CO2-rich syngas to methanol production.

Abstract

This invention discloses a method for preparing a Ga-intercalated modified CuZnAlGa-based hydrotalcite-derived catalyst and for improving CO conversion in the production of methanol from CO2-rich syngas. The preparation method involves co-precipitation of anionic Ga(OH)4... ‑ Direct intercalation into the interlayer of a hydrotalcite-like structure yields Ga(OH)4. ‑ An intercalated, layered double hydroxide-like precursor was developed. After high-temperature calcination and in-situ reduction in a hydrogen atmosphere, a structure was obtained in which Cu particles were spatially confined in multiple dimensions by oxides within a transverse layered framework and between longitudinal layered frameworks. This intercalated, layered double hydroxide-like structure possesses both high activity and high stability due to its multi-element active centers and confined structure, significantly improving the CO conversion rate in the production of methanol from carbon dioxide-rich syngas. The catalyst of this invention, after stabilization at a reaction temperature of 250 °C, retained over 97% catalytic activity after a 12-hour thermal shock at 300 °C. Furthermore, the highest CO conversion rate was achieved when the mass ratio of Ga₂O₃ between the layers was 2:4.

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