Catalytic Hydrogenation of Furfural to Downstream Products

The development and utilization of biomass resources as substitutes for traditional fossil resources are expected to meet society′s demand for cleaner production, industrial decarbonization, and a more sustainable future. Furfural is a key platform compound derived from agricultural byproducts such as corncobs and straw. It is primarily produced from the hemicellulose component of lignocellulose via dilute acid hydrolysis. Currently, furfural is widely used in the fine chemical, polyester, petrochemical refining, pharmaceutical, and pesticide industries, demonstrating its industrial viability. Due to its reactive aldehyde group and furan ring, along with other characteristic functional groups, furfural can be further converted through hydrogenation, ring-opening rearrangement, condensation, oxidation, and other reaction processes into alcohols, ketones, diols, and other high-value chemicals and high-density oxygenated fuels. Producing furfural downstream products improves its added value, extends the furfural industry chain, and contributes to decarbonization and carbon emission reduction in related fields, thereby supporting the global carbon neutrality goal. This paper reviews the recent research progress in the catalytic hydrogenation of furfural to alcohol products, including the preparation of furfuryl alcohol via hydrogenation and transfer hydrogenation. The former offers milder reaction conditions and simple operation, while the latter effectively mitigates safety risks associated with high-pressure hydrogen, such as flammability, explosivity, and diffusion. Furthermore, the paper summarizes research progress on the furfural-based preparation of cyclopentanone, cyclopentanol, pentanediol, tetrahydrofurfuryl alcohol, and other high-value chemicals. However, due to furfural′s chemical reactivity, the preparation of high-value chemicals such as cyclopentanone, cyclopentanol, pentanediol, and tetrahydrofurfuryl alcohol at high substrate concentrations remains challenging. Preventing side reactions, such as the polymerization of furfural, is crucial for future large-scale applications. Selective activation of furfural′s active functional groups and chemical bonds is essential for achieving high selectivity of target products. Finally, this paper discusses the challenges associated with furfural in thermal catalysis systems and industrial applications, and proposes future development directions. In recent years, new catalytic systems such as photocatalysis and electrocatalysis have seen significant progress. Applying these new methods to furfural conversion will provide new routes for utilizing furfural and other biomass-derived platform chemicals. Future directions in furfural catalytic hydrogenation include developing novel catalytic systems, suppressing side reactions, exploring new strategies, integrating traditional thermal catalysis with new catalytic systems, and employing innovative reactor designs. We believe that economically viable and sustainable reaction systems will be achieved in the future.