Development of a CuInZnZrOx Catalyst for Sorption-Enhanced CO2 Hydrogenation to Methanol

This study reports the mechanochemical synthesis of a highly efficient multicomponent CuInZnZrOx catalyst for the sorption-enhanced hydrogenation of CO2 to methanol. Through systematic optimization, the catalyst with a suitable indium loading of 0.5 wt % demonstrated favorable catalytic performance, achieving 22.5% CO2 conversion and 77.8% methanol selectivity under optimized reaction conditions (240 °C, 5 MPa, H2/CO2 = 10:1). Comprehensive structural characterization revealed that the incorporation of indium species significantly enhanced the dispersion of Cu nanoparticles while stabilizing the active Cu+/Cu0 sites, which are critical for both CO2 activation and methanol synthesis. The optimized CuIn0.5ZnZrOx catalyst exhibited remarkable long-term stability, maintaining over 95% of its initial activity during a 1000-h durability test, with a peak methanol space-time yield reaching 1974 g kgcat–1 h–1. Furthermore, when integrated with 13X zeolite in a sorption-enhanced reactor system, the catalyst system achieved a dramatic improvement in CO2 conversion (up to 65%), attributed to the in situ removal of the byproduct water that shifted the reaction equilibrium. This work not only elucidates the synergistic effects between indium modification and sorption-enhanced engineering but also presents a scalable and sustainable strategy for efficient CO2-to-methanol conversion, offering significant potential for industrial applications in carbon capture and utilization.