Identifying the Active Site and Structure–Activity Relationship in Hydrodeoxygenation of Ester to Alcohols over an Al2O3@CuZn Core–Shell Catalyst

Selective hydrogenation of fatty esters to high-value fatty alcohols is highly desirable for the utilization of natural oils. However, the hydration reaction of the support and hydrolysis reaction of the C–O bond can affect the selectivity of the targeted alcohol. Herein, core–shell Al2O3@Cu2Zn1-LDO is prepared via the in situ growth of CuZnAl-LDHs on Al2O3 microsphere substrates, followed by a calcination–reduction process. The catalyst achieves a methyl laurate (ML) conversion of 95% and selectivity of 98% for lauryl alcohol (LA) under mild conditions (4 MPa of H2 and 240 °C). In addition, the three-dimensional (3D) hierarchical structure of the Al2O3@Cu2Zn1-LDO catalyst enhances mass diffusion and transport, significantly improving catalytic performance and exhibiting excellent stability in the hydrogenation of fatty esters to fatty alcohols. The hydration reaction between Al2O3 and H2O produced during the hydrogenation of fatty acid esters is prevented successfully. Therefore, this work provides a new approach for designing newly structured Cu-based catalysts for the highly selective synthesis of fatty alcohols from natural oils.