{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T11:07:27Z","timestamp":1788865647290,"version":"build-2803163510"},"reference-count":46,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T00:00:00Z","timestamp":1649808000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002301","name":"Estonian Research Council","doi-asserted-by":"publisher","award":["RESTA11"],"award-info":[{"award-number":["RESTA11"]}],"id":[{"id":"10.13039\/501100002301","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>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 m2\/g and 1.4 cm3\/g, respectively.<\/jats:p>","DOI":"10.3390\/ma15082861","type":"journal-article","created":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T21:33:42Z","timestamp":1649885622000},"page":"2861","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":45,"title":["Characterization of Organosolv Lignins and Their Application in the Preparation of Aerogels"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8373-9895","authenticated-orcid":false,"given":"Piia","family":"J\u00f5ul","sequence":"first","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9511-2037","authenticated-orcid":false,"given":"Tran T.","family":"Ho","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8996-8912","authenticated-orcid":false,"given":"Urve","family":"Kallavus","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5492-248X","authenticated-orcid":false,"given":"Alar","family":"Konist","sequence":"additional","affiliation":[{"name":"Department of Energy Technology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristiina","family":"Leiman","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olivia-Stella","family":"Salm","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Kulp","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4040-3846","authenticated-orcid":false,"given":"Mihkel","family":"Koel","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7765-1707","authenticated-orcid":false,"given":"Tiit","family":"Lukk","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1002\/bit.26925","article-title":"Current achievements in the mechanically pretreated conversion of plant biomass","volume":"116","author":"Bychkov","year":"2019","journal-title":"Biotechnol. 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