Conversion of furfuryl alcohol to 1,5-pentanediol over CuCoAl nanocatalyst: The synergetic catalysis between Cu, CoOx and the basicity of metal oxides

A series of layered Cu-Co-Al hydrotalcite (LDHs) catalysts with different Cu/Co molar ratio were synthesized and applied for the hydrogenation of furfuryl alcohol to 1,5-pentanediol. The results indicated that the Cu0.2Co5.8/Al2O3 catalyst displayed an excellent catalytic efficiency compared to monometallic Co/Al2O3 or Cu/Al2O3 catalyst. The yield of 1,5-pentanediol reached 44.7% at 140°C, 4 MPa H2 within 2 h. In-situ XPS, H2-TPR, CO2-TPD analysis revealed that the high efficiency of this catalyst was attributed to the synergistic catalysis between the surface Cu0, CoOx and the basicity of metal oxides. Typically, Cu0 sites activate dissociated hydrogen, the basic sites anchor furfuryl alcohol by -OH to form an alcoholate species, inducing furfuryl alcohol with C2 oblique adsorption on the catalyst surface. The adjacent CoOx species adsorb and activate C2=C3 group in furfuryl alcohol. Subsequently, C2=C3 bond of furfuryl alcohol was partially hydrogenated, facilitating the cleavage C2-O1 bond to produce 1,5-pentanediol.