AUTHOR=Jõul Piia , Järvik Oliver , Lees Heidi , Kallavus Urve , Koel Mihkel , Lukk Tiit 

TITLE=Preparation and characterization of lignin-derived carbon aerogels

JOURNAL=Frontiers in Chemistry

VOLUME=Volume 11 - 2023

YEAR=2024

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2023.1326454

DOI=10.3389/fchem.2023.1326454

ISSN=2296-2646

ABSTRACT=Lignin is considered a valuable renewable resource to build new chemicals and materialsresins and polymers particularly. The aromatic nature of lignin suggests a synthetic route to organic aerogels (AG) similar to the aqueous polycondensation of resorcinol with formaldehyde (FA). The structure and reactivity of lignin largely depend on the severity of the isolation method used which challenges the development of new organic and carbon materials.The resorcinol aerogels are considered as a source of porous carbon material, while ligninbased aerogels also possess a great potential for the development of carbon materials, having a high carbon yield with high specific surface area and microporosity. In the present study, the birch hydrolysis lignin and organosolv lignin extracted from pine were used to prepare AG with formaldehyde, with the addition of 5-methylresorcinol in the range of 75-25% yielding monolithic mesoporous aerogels with a relatively high specific surface area, up to 343.4 m 2 /g. The obtained lignin-based AGs were further used as raw material for the preparation of porous carbon aerogels (CAs) under well-controlled pyrolysis conditions with the morphology, especially porosity and specific surface area, being dependent on the origin of lignin and its content in the starting material.