Abstract
? 2022 Elsevier B.V.Tailoring the hydrodeoxygenation capacity via the regulation of the electronic structure of the active site is still a significant challenge for hydrogenation of oxygenated substrates. Herein, we report the highly efficient bimetallic CoNi/HAP catalysts to promote the catalytic transfer hydrodecarbonylation of methyl stearate to heptadecane. Multiple characterizations reveal that the CoNi alloy nanoparticles with fcc structure exhibit strong electron coupling effect and enhanced adsorption of methyl stearate, leading to the improvement of catalytic activity. Specifically, the introduction of Ni changes the reaction pathway from methyl stearate → octadecanol over the Co/HAP catalyst to methyl stearate → heptadecane over CoNi/HAP catalysts. In situ Fourier transform infrared spectra, reaction kinetics and density functional theory calculation show that the heptadecane is mainly generated through hydrodecarbonylation (-CO) rather than hydrodecarboxylation (-COO) because the C[sbnd]C bond cleavage of oxygenated intermediate (RCH2CO) is greatly facilitated over the Ni active site of electron reconstructed CoNi alloy nanoparticles. Finally, the Co5Ni5/HAP catalyst exhibits excellent conversion (99.4%), heptadecane selectivity (98.2%) and catalyst stability. These insights revealed here could pave the way for the rational development of catalyst with high catalytic performance in the catalytic transfer hydrogenation system of fatty acids/esters.
NSTL
Elsevier