Characterization of Organosolv Lignins and Their Application in the Preparation of Aerogels

The production of novel materials and value-added chemicals from lignin has received considerable attention in recent years. Due to its abundant occurrence in nature, there is a growing interest in utilizing lignin as a feedstock for functional materials production, for example aerogels. Much like in the synthesis of phenol-based resins, the vacant ortho positions of the aromatic rings in lignin can crosslink with formaldehyde and form polymeric gels. After drying the hydrogels with supercritical CO2, highly porous aerogels are obtained. Current study focuses on the preparation and thorough parametrization of organosolv lignins from different types of lignocellulosic biomass (aspen, pine, and barley straw) as well as their utilization for the preparation of lignin-5-methylresorcinol-formaldehyde aerogels. The thorough structural characterization of the obtained aerogels was carried out by gas adsorption, IR spectroscopy, and scanning electron microscopy. The obtained lignin-based monolithic mesoporous aerogels had specific surface areas and total pore volumes in the upward ranges of 450 m(2)/g and 1.4 cm(3)/g, respectively.

Automated summary

The production of novel materials and value-added chemicals from lignin has received significant attention in recent years. Lignin, due to its abundant occurrence in nature, has been identified as a potential feedstock for the production of functional materials such as aerogels. This study focuses on the preparation and characterization of lignin-based aerogels using different types of lignocellulosic biomass. The obtained aerogels showed promising properties with high specific surface areas and total pore volumes.