Selective Hydrogenolysis Of Aryl Ether Bond Over Ru-Fe Bimetallic Catalyst

RuFe/CeO2 catalysts were studied in the hydrodeoxygenation (HDO) of diphenyl ether (DPE). We find that the hydrogenation reactivity is favored over 2Ru/CeO2, leading to the formation of dicyclohexyl ether and cyclohexyl phenyl ether as main products. Addition of oxophilic Fe inhibits the hydrogenation of aromatic rings but enhances the hydrogenolysis of C-O bonds to produce benzene and phenol as well as cyclohexane and cyclohexanol formed from subsequent hydrogenation of phenol. similar to 92 % selectivity to C-O bond ruptured products were achieved with similar to 21 % yield toward aromatics (benzene and phenol) on 0.5Ru1.5Fe/CeO2 catalyst. Characterization using X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR) reveals that the adsorption of aromatic ring is weakened on the RuFe alloy surface compared to Ru which leads to reduced hydrogenation of arenes, while oxophilic nature of Fe facilitates the adsorption of the aryl-ether bond that enhances the hydrogenolysis of C-O bonds in DPE.