Reduced Cu–Co–Al Mixed Metal Oxides for the Ring-Opening of Furfuryl Alcohol to Produce Renewable Diols

Abstract

The ring-opening of furfuryl alcohol to diol products, including 1,2-pentanediol and 1,5-pentanediol, is investigated over reduced Cu–Co–Al mixed metal oxides in a liquid phase batch reactor under H2 pressure. These catalysts are synthesized through the calcination of layered double hydroxides (LDH) to yield well-dispersed, porous mixed metal oxides, which upon reduction displayed activity toward diols, mainly the valuable monomer 1,5-pentanediol. The addition of Cu facilitated the reduction of Co oxide species at lower temperatures, and under optimized conditions, a yield toward 1,5-pentanediol of 44% (total diol yield of 62%) was achieved. Various characterization techniques including temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS) are employed to elucidate the structure of the catalysts, suggesting the formation of both metallic (Co and Cu) and oxide (CoO) species after reduction and passivation. Ultimately, this study demonstrates...