Hydrogenation of 5-hydroxymethylfurfural into 2,5-bis (hydroxymethyl)furan over mesoporous Cu-Al2O3 catalyst: From batch to continuous processing

Abstract

Biomass-derived monomers have received growing attention from sustainable polymer industry. Particularly, diol compounds can be formed from furfural (FAL) and 5-hydroxymethylfurfural (HMF). Herein, the mesoporous Cu-Al2O3 catalyst (meso-CuA) prepared by solvent-deficient precipitation was evaluated to be efficient in selective hydrogenation of FAL and HMF to furfuryl alcohol to 2,5-bis (hydroxymethyl)furan (BHMF), respectively, at temperatures of lower than 100 degrees C and high H-2 pressures. Owing to unique pore structure and small-sized copper nanoparticles entangled with alumina, meso-CuA turned out to be superior to other supported Cu catalysts in the hydrogenation of HMF to BHMF. Moreover, meso-CuA showed highly durable performance at the BHMF yield of higher than 90% at 100 degrees C, 50 bar H-2, and weight hourly space velocity of 0.2 h(-1) over time-on-stream of 100 h. The stability was also confirmed with the HMF feed containing 1 wt% of water that proved to have more considerable effect than other possible impurities. Centering around a catalytic reactor packed with meso-CuA, a process scheme from HMF feed to pure BHMF solid was developed at a production scale of 100 kg per day. The present results can contribute to designing commercial process of BHMF production from HMF and further, real biomass.