Gas-Phase Hydrogenation of Furfural to Furfuryl Alcohol over Cu-ZnO-Al2O3 Catalysts Prepared from Layered Double Hydroxides

JIMÉNEZ-GÓMEZ, CARMEN P.; R. BERTOLINI, GUILLERMO; MAIRELES-TORRES, PEDRO; CECILIA, JUAN ANTONIO

Catalysts

MDPI AG

Lugar: Basel; Año: 2020 vol. 10

Several layered double hydroxides (LDHs) with general chemical composition(Cu,Zn)1􀀀xAlx(OH)2(CO3)x/2mH2O have been synthesized by the co-precipitation method,maintaining a (M2+/M3+) molar ratio of 3, and varying the Cu2+/Zn2+ molar ratio between 0.2and 6.0. After calcination and reduction steps, Cu/ZnO/Al2O3 catalysts were synthesized. Thesecatalysts were characterized by X-ray diraction (XRD), transmission electron microscopy (TEM),H2 thermoprogrammed reduction (H2-TPR), N2 adsorption-desorption at 􀀀196 C, N2O titration,X-ray photoelectron miscroscopy (XPS), NH3-thermoprogramed desorption (NH3-TPD) and CO2-thermoprogrammed desorption (CO2-TPD). The characterization data revealed that these catalysts are mainly meso-and macroporous, where Cu, ZnO and Al2O3 are well dispersed. The catalytic results show that these catalysts are active in the gas-phase hydrogenation of furfural, being highly selective to furfuryl alcohol (FOL) and reaching the highest FOL yield for the catalyst with a Cu2+/Zn2+ molar ratio of 1. In an additional study, the influence of the aging time on the synthesis of the LDHs was also evaluated. The catalytic data revealed that the use of shorter aging time in the formation of the LDH has a beneficial eect on the catalytic behavior, since more disordered structures with a higher amount of available Cu sites is obtained, leading to a higher yield towards FOL (71% after 5 h of time-on-stream at 210 C).