Among all the materials resulting from the recovery of biomass, humin coproducts are produced today on a large scale, particularly in the sugar industry and biorefineries. Humins formation, with typical yields between 10 and 50 wt %, significantly reduces the efficiency and economic viability of the processes. With their complex structure, low solubility, and low reactivity, their valorization constitutes a real challenge. This paper aims to establish the proof of concept for the transformation of recalcitrant humins into high-value-added biobased products using polyoxometalate-based ionic liquids (POM-ILs) under "mild" conditions. In this contribution, the POM-IL (P