Furfural hydrogenation to 2-methylfuran over efficient sol-gel copper-cobalt/zirconia catalyst

Abstract

2-Methylfuran (MF) is a candidate to be a high-quality fuel additive. For the first time, efficient Co-Cu/ZrO2 catalysts were prepared by the sol-gel method and herein used for MF synthesis from furfural. Although a 9.2% MF yield and no MF was obtained using Cu/ZrO2 and Co/ZrO2, respectively, a 77.5% MF yield was observed at 200 degrees C, under 1.5 MPa initial H-2 pressure for 4 hours using a Co-Cu/ZrO2 catalyst. The Co amount was changed in the catalyst structure and the effect of the Co amount on furfural hydrogenation was investigated. The most effective catalyst was the Co-Cu/ZrO2 catalyst, with 0.08 g/g (8 mass%) Cu and 0.118 g/g (11.8 mass%) Co. The activity tests of the catalysts were carried out for hydrogenation of furfural to MF by changing reaction parameters such as pressure, loading of catalyst, temperature, and time. A 94.1% MF yield was achieved in the presence of the Co-Cu/ZrO2 catalyst with 0.08 g/g (8 mass%) Cu and 0.118 g/g (11.8 mass%) Co at 200 degrees C for 6 hours under 1.5 MPa H-2 pressure. The catalyst also showed good reusability properties after the fifth use. The catalysts were characterized by Brunauer-Emmet-Teller method, X-ray diffraction, X-ray photoelectron spectroscopy, and temperature programmed reduction techniques.