Applications of hydroiodic acid catalysis for hydrodeoxygenation of biomass

<p indent="0mm">Biomass, as a green and renewable resource, has the potential to replace fossil resources for the production of high-value chemicals and biofuels. Due to the high oxygen content in biomass feedstocks, hydrogenolysis (HDO) reactions become a key step in their conversion process. Hydroiodic acid (HI) can effectively catalyze the hydrogenolysis of biomass under mild conditions due to its strong nucleophilicity and reductive properties, and in some biomass conversion processes, it can achieve the application of metal-free catalysis. This article reviews the research progress of the “HI-metal catalyst-H₂” catalytic system and the “HI-hydrogen donor” metal-free catalytic system in biomass HDO reactions. Future explorations of the HI system should focus on mechanism studies, expand the application scope of HI in the directed conversion of biomass, and pay attention to the environmental impact of the reaction process.