Humins from biorefineries as thermo-reactive macromolecular systems

Conversion of lignocellulosic biomass often brings along the formation of several side products. Among these, the formation of a black and viscous co-product so-called humins is observed due to acidic treatment of polysaccharides. To improve the efficiency of this process from an economical and environmental prospective, new solutions for humins valorization are urgently needed. This work focuses on the comprehensive understanding of humins with special emphasis on their structure/properties relations. Humins were subjected to different thermal treatments and were investigated by means of structural, thermoanalytical and rheological characterizations. The structure and composition of humins is very diverse and depends on the thermochemical conditions. Upon sufficient heating, humins will change into a non-reversible and more branched furanic structure with a relatively high glass transition temperature (Tg > 65 °C). It means that humins can be easily processed for preparing thermoset-like resins