Furfural is a renewable platform compound that can be derived from lignocellulosic biomass. The highly functionalized molecular structure of furfural enables us to prepare a variety of high value-added chemicals, which will help realize biomass high-value utilization, and alleviate energy and environmental problems. This paper reviews the research progress on furfural production and upgrading to C5 chemicals from the catalyst perspective. The emphasis is placed on summarizing and refining the catalytic mechanism and in-depth analysis of available data. Specifically, the reaction mechanism of furfural production and upgrading is summarized firstly from the perspective of reaction pathways and reaction kinetics. Then, the available data are further processed to evaluate the actual reaction efficiency of different catalytic systems from multiple dimensions. Finally, based on statistical analysis, the challenges and opportunities of furfural-based research are proposed.

With the rapid development of biorefinery technology, the efficient conversion of lignocellulose into high-value platform chemicals is of great significance for enhancing the value of renewable carbon resources. In this study, a hydroxyl-functionalized covalent organic framework (COF), TAPB-DHPA, was synthesized via an in situ method and innovatively applied to the catalytic conversion of xylo-oligosaccharides (XOS) into furfural. The results demonstrated that TAPB-DHPA possesses a large specific surface area, a well-developed porous structure, and excellent thermal stability, with abundant Brønsted acid (B acid) sites, exhibiting outstanding catalytic activity. Under optimal conditions, including a catalyst loading of 0.16 wt%, a reaction temperature of 180 °C, and a reaction time of 3 h, a furfural yield of up to 65.4% was achieved. The high selectivity was primarily attributed to the p-π conjugation effect between the benzene ring and the phenolic hydroxyl group, which enhanced the ionization ability of hydroxyl hydrogen, thereby effectively promoting the hydrolysis of XOS and subsequent dehydration. Furthermore, TAPB-DHPA exhibited excellent recyclability and stability, maintaining a furfural yield of over 59.9% after six cycles. This study provides new insights into the application of functionalized COF in biomass catalytic conversion and contributes to the green transformation of the pulp and paper industry into a biorefinery-based model.

The utilization of abundant and renewable cellulose as an alternative to fossil resources provides a promising pathway for the sustainable production of bio-based chemicals. The development of multifunctional catalysts is key to achieving the efficient conversion of cellulose into high value-added chemicals. In this study, a combination of in situ and post-synthetic strategies was employed to synthesize functionalized covalent organic frameworks (COFs). Using aldehyde monomers containing phenolic hydroxyl groups and amine monomers with triazine structure as raw materials, COFs (TATP) rich in acidic active sites were successfully synthesized via the solvothermal method. Subsequently, a multifunctional catalyst (Ru-WO_x/TATP) capable of catalyzing hydrolysis, hydrogenolysis, and hydrogenation reactions was developed by loading active metals ruthenium (Ru) and tungsten (W). Finally, this catalyst was applied to the research on one-step catalytic conversion of cellulose to ethylene glycol (EG). The results showed that Ru–WO_x/TATP exhibited good crystallinity and thermal stability, and showed excellent catalytic performance and high selectivity for EG in the one-pot aqueous-phase conversion of cellulose. Under the optimal reaction conditions of 245 °C, an initial hydrogen pressure of 5 MPa, a substrate concentration of 1%, and a reaction time of 3 h, complete cellulose conversion was achieved, with an ethylene glycol yield of up to 62.9%. This work innovatively developed a functionalized COF with catalytic capabilities for hydrolysis, hydrogenolysis, and hydrogenation, and applied it to the catalytic conversion of cellulose into EG, thereby expanding the application scope of COFs in biomass catalysis.