Transfer hydrogenolysis of aromatic ethers promoted by the bimetallic Pd/Co catalyst

• Published in: Catalysis today 2020-11, Vol.357, p.511-517
• Main Authors: Mauriello, F., Ariga-Miwa, H., Paone, E., Pietropaolo, R., Takakusagi, S., Asakura, K.
• Format: Article
• Language: English
• Subjects: Aromatic ethers; Cobalt; Heterogeneous catalysis; Lignin; Palladium; Transfer hydrogenolysis
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/j.cattod.2019.06.071

[Display omitted] •Pd/Co catalyst can promote the transfer hydrogenolysis of aromatic ethers.•The Pd/Co catalysts is characterized by the presence of bimetallic Pd-Co ensembles.•Benzyl phenyl ether is fully converted into toluene and cyclohexanol.•The Pd/Co catalyst can be recycled up to six times without any activity loss. The transfer hydrogenolysis of lignin derived aromatic ethers (benzyl phenyl ether, phenethyl phenyl ether and diphenyl ethers) have been investigated by using the coprecipitated Pd/Co as heterogeneous catalyst and 2-propanol as H-donor/solvent. A quantitative conversion of benzyl phenyl ether into toluene and cyclohexanol was obtained after 180 min at 240 °C. The bimetallic Pd/Co catalyst is, by far, more efficient if compared to commercial Pd/C and Co-based catalytic systems showing, at the same time, a good reusability. The enhanced ability in the CO bond cleavage in aromatic ethers is related to the formation of bimetallic Pd-Co ensembles, arisen from the preparation procedure adopted, as confirmed by a complete physico-chemical characterization that includes XRD, SEM, TEM, H2-TPR, XPS and EXAFS analysis.