CO₂‐Hydrogenation to Methanol over CuO/ZnO Based Infiltration Composite Catalyst Spheres

Abstract

Multiple active component catalysts for efficient conversion of CO2 to Methanol (MeOH) are synthesized through coating γ‐Al2O3 carrier spheres by incipient wetness impregnation method (IWI). The well‐known bimetallic Copper Oxide/Zinc Oxide (CuO/ZnO) are promoted in three steps, first by Cerium Oxide (CeO2), then additionally with Zirconium Oxide (ZrO2) and finally with Calcium Oxide (CaO) resulting in four carrier catalysts with high surface area and catalyst pore. Quaternary and quinary carrier catalysts promoted with moderate CeO2, ZrO2 in the quaternary (20% CZCZ) and additionally with CaO (20% CZCZC) in the quinary catalysts demonstrate high CO2‐conversion ratios (16.2% and 18.7%) and space time yields (0.51 and 0.47 gMeOH h‐1 gCatalyst‐1) at 5 MPa and 250 °C reactor temperature. The high conversion ratios (XCO2) and good methanol space‐time‐yields (STYMeOH) are attributed to enhanced copper dispersion and several multi metal oxide component interactions essential to enhance CO2‐activation and ‐conversion through the catalytic systems as well as very high overall surface area. Compared to related studies, the carrier catalysts show superior conversion rates, proving the effectiveness of the introduced multi‐component carrier catalyst and extending the understanding of infiltrate composites as possible large‐scale application alternatives to precipitated MeOH catalyst systems.