FeSBA-15-supported ruthenium catalyst for the selective hydrogenolysis of carboxylic acids to alcoholic chemicals

Ordered mesoporous FeSBA-15-supported Ru catalysts are characterized by N-2 adsorption-desorption isotherm, H-2-temperature-programmed reduction, X-ray fluorescence, X-ray diffraction, X-ray photo-electron spectroscopy, and transmission electron microscopy analyses. Results suggest the co-existence of Fe oxide species highly dispersed in the frameworks of SBA-15 and Ru-Fe bimetallic nanoparticles. The concentration of Fe species is low and in the form of Ru-Fe alloys located on the catalyst surfaces following reduction pretreatment in 5% H-2-95% N-2 flow at 623 K for 4 h. The as-reduced Ru/FeSBA-15 catalysts efficiently and selectively hydrogenolyze short-chain carboxylic acids (e.g., acetic acid, propionic acid, butyric acid, levulinic acid, and lactic acid) to their corresponding alcoholic chemicals. Results indicate that 2% Ru/FeSBA-15 catalyst with 1.07% Fe content yields the highest performance and excellent stability, yielding 92.5% conversion of acetic acid and 85.2% selectivity to ethanol under optimized conditions. The improved catalytic performance of the FeSBA-15-supported Ru catalyst is mainly attributed to the coherent interactions between Fe and Ru species, as well as to the high dispersion of Fe oxides in the SBA-15 framework. (C) 2014 Elsevier B.V. All rights reserved.