{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T02:25:20Z","timestamp":1769912720783,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,19]],"date-time":"2025-05-19T00:00:00Z","timestamp":1747612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["2022.08091.PTDC"],"award-info":[{"award-number":["2022.08091.PTDC"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Lignin, a complex aromatic biopolymer abundant as waste in biorefineries and the pulp and paper industry, holds significant potential for valorization. This study presents the oxidative depolymerization of Lignoboost lignin (LB) using H2O2 under mild, solvent- and catalyst-free, inherently acidic conditions at 50\u201370 \u00b0C. The process aimed to produce functionalized low-molecular-weight oligomers, retaining aromaticity, and aliphatic dicarboxylic acids, rather than complete monomerization. The depolymerized LB was rich in aromatic dimers-trimers (68.6 wt.%) with high functionalization (2.75 mmol\/g OHphen, 3.58 mmol\/g OHcarb, 19.5 wt.% of H in -CH=CH-), and aliphatic dicarboxylic acids (53.4 wt.% of monomers). Acidic conditions provided higher depolymerization and functionalization than alkaline, alongside simplified product recovery. The process was also successfully applied to Kraft lignin, demonstrating versatility and robustness even with higher polymeric content feedstocks. The optimized conditions were scaled up (\u00d725), improving efficiency and yielding Mw 464 g\/mol and \u0110 1.3. As proof of concept, the scaled-up product underwent radical crosslinking, resulting in a new biopolymer with higher thermal stability than LB (54.2 wt.% residual mass at 600 \u00b0C versus 36.1 wt.%). This green, scalable process enhances lignin valorization by producing functionalized low-molecular-weight lignin oligomers and dicarboxylic acids that can be used independently or together to form crosslinked networks.<\/jats:p>","DOI":"10.3390\/ijms26104872","type":"journal-article","created":{"date-parts":[[2025,5,19]],"date-time":"2025-05-19T11:54:26Z","timestamp":1747655666000},"page":"4872","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Acidic Oxidative Depolymerization Towards Functionalized Low-Molecular-Weight Lignin and High-Value-Added Aliphatic Monomers: Operating Conditions, Scale-Up, and Crosslinking"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9476-5731","authenticated-orcid":false,"given":"Marta C.","family":"Louren\u00e7o","sequence":"first","affiliation":[{"name":"Centro de Recursos Naturais e Ambiente (CERENA), Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8103-4047","authenticated-orcid":false,"given":"Talita","family":"Nascimento","sequence":"additional","affiliation":[{"name":"Centro de Recursos Naturais e Ambiente (CERENA), Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9852-8940","authenticated-orcid":false,"given":"Pedro Jos\u00e9 Sanches","family":"Filho","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural (CEQ), Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2947-1186","authenticated-orcid":false,"given":"Ana C.","family":"Marques","sequence":"additional","affiliation":[{"name":"CERENA, Department of Chemical Engineering, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0344-7655","authenticated-orcid":false,"given":"Marta","family":"Ramos-Andr\u00e9s","sequence":"additional","affiliation":[{"name":"Centro de Recursos Naturais e Ambiente (CERENA), Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4385","DOI":"10.1002\/cssc.202001324","article-title":"Lignin Source and Structural Characterization","volume":"13","author":"Sun","year":"2020","journal-title":"ChemSusChem"},{"key":"ref_2","unstructured":"(2025, May 01). Research and Markets Lignin Market: Analysis by Type, Form, Applications, Region Size, Trends and Forecast up to 2029. 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Protoc."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/10\/4872\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:35:21Z","timestamp":1760031321000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/10\/4872"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,19]]},"references-count":35,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2025,5]]}},"alternative-id":["ijms26104872"],"URL":"https:\/\/doi.org\/10.3390\/ijms26104872","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,19]]}}}