Hydrogenation efficiency of highly porous Cu-Al oxides derived from dealuminated LDH in the conversion of furfural to furfuryl alcohol

As-synthesized Cu-Al LDH was dealuminated by treating with Ammonium hexafluorosilicate (AFS) and calcined to obtain Cu-Al oxide. Cu species from 5 to 20 wt% was impregnated on Cu-Al oxide derived from dealuminated Cu-Al LDH. Resulting samples were characterized by XRD, AAS, BET, TEM, TPR and XPS techniques. Copper species impregnated on dealuminated Cu-Al oxide exhibit enhanced activity in hydrogenation of furfural (FAL) to furfuryl alcohol (FOL). Hydrogen uptake and FAL conversion were found to increase proportionately as the copper species dispersed in the pores vary from 5 to 15 wt%. A maximum yield of 87 mol% FAL was observed with 15 wt% Cu loaded sample. Percent occupancy of the copper active species in the pores is calculated by the decrease in pore volume. A factor called pore occupancy hydrogenation efficiency is introduced to explain the FAL conversion ability of the copper loaded mixed oxides. In contrast, mixed oxides derived from Cu-Al LDH without dealumination showed moderate conversion. (C) 2018 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.