Continuous hydroxyketone production from furfural using Pd–TiO2 supported on activated carbon

Abstract

Pd–TiO₂, Pd–Cu and Pd–Fe activated carbon (AC) supported catalysts were employed for continuous selective hydrogenation of furfural. The effect of reaction parameters on product selectivity and space time yield (STY) was determined. Weak acid sites, generated by the Pd–TiO₂ catalyst opened the furan ring and resulted in a STY of 134 g L_cat⁻¹ h⁻¹ (610 g kg_cat⁻¹ h⁻¹) and 39% selectivity to 5-hydroxy-2-pentanone (5H2P), a hydrogenation product of furan ring opening, in a short residence time (7.6 min) at 180 °C and 300 psig. The Pd–Cu and Pd–Fe catalysts were selective towards tetrahydrofurfuryl alcohol and furfuryl alcohol. A STY of 259 g L_cat⁻¹ h⁻¹ (1182 g kg_cat⁻¹ h⁻¹) and 42% selectivity to furfuryl alcohol was achieved in the presence of the Pd–Cu catalyst at 180 °C and 300 psig (3.8 min). The Pd/TiO₂/AC catalyst shows promise for continuous production of 5H2P, a building block for many drugs and a precursor to 1,4-pentanediol.