Work

Aerobic ethanol oxidation by magnetic inductive heating of Pd NPs supported onto Ni foam

Year: 2026

Type: preprint

Abstract: Selective aerobic oxidation of ethanol to acetic acid is an attractive example of the conversion of biomass-derived alcohol value-added chemicals. In this context, conventional liquidphase processes often rely on harsh conditions, long reaction times, inefficient external heating and limited catalyst recovery. Herein, a radically new strategy for acetic acid synthesis from ethanol is proposed and demonstrated. The catalyst used is designed not only as the active phase for chemical transformation, but also as the element responsible for local heat generation. Pd nanoparticles were immobilised onto magnetically-responsive Ni foam, affording a macroscopic, flow-compatible architecture that overcomes key limitations found for dispersed or powdered systems, including aggregation, active-phase loss and difficult reuse. Using a low amplitude alternating magnetic field of 9.2 mT, which corresponds to a lower magnetic flux density value than normally used for dispersed magnetic nanocatalyst, the Pd@Ni-foam system reached 90 % ethanol conversion after 8 h, while the acetic acid selectivity was >98 % already after 2 h reaction time. In analogous conditions, conventional heating was significantly less effective than magnetic induction, highlighting the advantage of delivering thermal energy directly at the Pd/liquid interface, thereby preserving ethanol availability at the active sites while limiting substrate evaporation. The structured catalyst showed direct reusability without regeneration, and analysis of the recovered catalyst revealed neither Pd NPs sintering, nor detectable Pd loss. By combining catalytic activity, lowfield magnetic responsiveness, stability, reduced bulk heating and continuous flow operation within a single tuneable material, a new approach to heterogeneous catalysis has been introduced, opening a modular route toward electrified, intensified and more efficient liquidphase transformations of renewable and volatile substrates, such as ethanol.

Source: ChemRxiv

DOI: 10.26434/chemrxiv.15010175/v1