Regioselective Upgrading of Furfural into 2-Methyl Furan over Cobalt Confined in Microporous Carbon Spheres

Abstract

The selective hydrogenative upgrading of lignocellulose-derived furanic molecules into 2-methylfuran (2-MF) represents an appealing yet challenging goal, primarily due to the competing furan ring on metal surfaces, especially at low temperatures. This issue significantly limits the overall yield of 2-MF. Herein, we present an efficient regioselective strategy to maximize the 2-MF yield from furfural hydrodeoxygenation by encapsulating active cobalt species within microporous carbon spheres (Co@MCS). Both experimental results and theoretical calculations reveal that the micropores in MCS act as shape-selective fillers, guiding furfural’s access to the cobalt sites in a small, tilted configuration rather than a large, coplanar arrangement, thereby significantly suppressing the side reaction of ring hydrogenation. Remarkably, the high 2-MF productivity of 1.7 g_2-MF g_Cat.^–1 h^–1 with nearly 100% selectivity is achieved over Co@MCS at 130 °C and 2 MPa of p_H2, overcoming all previously reported results. This work provides valuable insights for designing catalysts with high selectivity for the conversion of lignin-derived platform chemicals. Furthermore, the concept of confined catalysis holds promise for broader application in other industrial catalytic processes.