Sep 16 2020
A team of researchers from the Institute of Solid-State Physics, Hefei Institutes of Physical Science has recently developed a non-precious alloy catalyst that has superior catalytic stability selectivity, and activity for selective hydrogenation (SH) of cinnamaldehyde (CAL).
(a). Schematic illustration of synthetic procedure of FeXCo@NC; (b). TEM image (insets: high-magnification TEM image and Fe-Co NPs size distribution); (c) XRD pattern; (d-e) HAADF-STEM, corresponding elemental mapping images and line profile of Fe-Co NPs. Image Credit: LV Yang.
Cinnamyl alcohol (COL) is an important compound that is in great demand by the pharmaceutical, perfume, and flavoring industries. However, selective hydrogenation of CAL to COL is hindered by unfavorable thermodynamics that results in low selectivity toward COL.
Moreover, when an organic solvent is used in COL production, it contaminates the environment and involves post-production separation.
Therefore, to enhance the selectivity of CAL hydrogenation, transition-metal/noble-metal (platinum (Pt) is mostly used) bimetallic catalysts are used to create synergetic electronic effects that thermodynamically favor the hydrogenation of C=O in CAL. But the use of rare and costly noble metals is not desirable.
For the first time, the team developed a solution-based metal ion impregnation method and innovatively integrated it with pyrolysis to obtain the controllable prosecution of highly dispersed Fe-Co alloy nanoparticles (NPs) on N-doped graphitic carbon support.
According to the researchers, the COL selectivity and CAL conversion efficiency were respectively supported by the presence of Co and Fe, whereas the synergism of the alloyed Fe-Co provided a solution to acquire high COL selectivity and CAL conversion efficiency at the same time.
The team also discovered that the water (H2O) played a crucial role in CAL conversion. With regard to CAL conversation, greater solvent polarity translates to higher CAL conversion efficiency.
With regard to COL selectivity, the researchers categorically verified that the promotional effect of H2O solvent considerably improved the hydrogenation on C=O and, at the same time, inhibited the hydrogenation on C=C.
The Natural Science Foundation of China and the Postdoctoral Science Foundation of China have funded the study.