Effective and Selective Hydrogenation of Methyl Acrylate to Methyl Propionate on Single-Atom Nickel Catalyst

Development of highly efficient, selective, and stable single-atom catalyst (SAC) is an important research hotspot in the field of hydrogenation, due to the atomic utilization of active component. In this study, an effective single-atom nickel catalyst with a specific coordination structure of Ni─N₄ was constructed using Ni-containing ZIF-8 as precursor for efficient hydrogenation of methyl acrylate to methyl propionate in the fixed-bed reactor. Multiple characterization techniques including HAADF-STEM, H₂-TPR, XRD, and XAFS were utilized to systematically analyze the structure and physicochemical properties of as-prepared catalyst series. The effects of catalyst preparation and hydrogenation conditions on the catalytic performance were evaluated and further optimized. As a result, the turn of frequency (TOF) could reach up to 200.8 h^-1 for methyl propionate production, with catalytic selectivity of 100%. In situ IR experiments were performed to monitor the hydrogenation mechanism on the catalyst surface, as well as kinetic studies for confirmation of reaction order and activation barrier. This study will provide a new strategy for the design and of non-noble metal SAC for the hydrogenation of methyl acrylate.