{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T08:31:42Z","timestamp":1786609902001,"version":"build-2736575974"},"reference-count":27,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T00:00:00Z","timestamp":1786579200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&D Program of China","doi-asserted-by":"publisher","award":["2022YFC3902405"],"award-info":[{"award-number":["2022YFC3902405"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Project of China Huaneng Group Co., Ltd.","award":["HNKJ24-H111"],"award-info":[{"award-number":["HNKJ24-H111"]}]},{"award":["HNKJ24-H111"],"award-info":[{"award-number":["HNKJ24-H111"]}],"id":[{"id":"https:\/\/ror.org\/059wz5438","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study investigates the degradation behavior of decommissioned wind turbine blade composites in organic fluid systems, with particular focus on the subcritical acetic acid route. Supercritical acetone and supercritical n-butanol were used as screening media, while retired-blade glass fiber-reinforced polymer (GFRP) composites and laboratory-prepared glass fiber\/epoxy composites were used to compare resin removal and fiber recovery behavior. The screening results showed that supercritical acetone and supercritical n-butanol caused partial matrix degradation but left visible organic residues on recovered fibers, whereas subcritical acetic acid produced cleaner fiber surfaces under lower-pressure conditions. The effects of temperature and reaction time were then analyzed in the subcritical acetic acid system. At 280 \u00b0C for 60 min, the epoxy resin degradation rate reached 99.81%, and the recovered glass fibers retained 96.49% of their tensile strength. Gas chromatography\u2013mass spectrometry (GC\u2013MS) analysis indicated that the liquid products mainly contained phenols, esters, and other oxygenated organics, with bisphenol A derivatives as representative components. These products suggest a coupled degradation process involving epoxy network swelling, bond cleavage, fragment release, and secondary acetylation in acetic acid. The boiling-point difference between acetic acid and the main degradation products, together with the product distribution obtained after recovered-acid addition, indicates the potential of acetic acid reuse. These findings support subcritical acetic acid as a promising medium for resin removal and glass-fiber recovery from decommissioned wind turbine blade composites.<\/jats:p>","DOI":"10.3390\/ma19163428","type":"journal-article","created":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T08:06:16Z","timestamp":1786608376000},"page":"3428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Degradation Characteristics of Decommissioned Wind Turbine Blade Composites in Subcritical and Supercritical Fluids"],"prefix":"10.3390","volume":"19","author":[{"given":"Yu","family":"Ru","sequence":"first","affiliation":[{"name":"School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"},{"name":"Beijing Huaneng Yangtze Environmental Technology Research Institute Co., Ltd., Beijing 102209, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuzhe","family":"Li","sequence":"additional","affiliation":[{"name":"Beijing Huaneng Yangtze Environmental Technology Research Institute Co., Ltd., Beijing 102209, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nan","family":"Li","sequence":"additional","affiliation":[{"name":"Beijing Huaneng Yangtze Environmental Technology Research Institute Co., Ltd., Beijing 102209, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingchun","family":"Huang","sequence":"additional","affiliation":[{"name":"School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yifan","family":"Bao","sequence":"additional","affiliation":[{"name":"Huaneng Yangtze Environmental Technology Co., Ltd., Beijing 102209, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Qiao","sequence":"additional","affiliation":[{"name":"School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106107","DOI":"10.1016\/j.resconrec.2021.106107","article-title":"Development of sustainable microwave-based approach to recover glass fibers for wind turbine blades composite waste","volume":"179","author":"Rani","year":"2022","journal-title":"Resour. 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Embodied energy in pyrolysis and solvolysis approaches to recycling for carbon fiber-epoxy reinforced composite waste streams. Recycling, 7.","DOI":"10.3390\/recycling7010006"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1007\/s11029-022-10048-9","article-title":"Recycling of fiberglass fillers obtained from polymer composites based on an epoxy vinyl ester binder","volume":"58","author":"Protsenko","year":"2022","journal-title":"Mech. Compos. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"012009","DOI":"10.1088\/1742-6596\/2353\/1\/012009","article-title":"Recycling of the polymer composite fillers in amino alcohol medium","volume":"2353","author":"Protsenko","year":"2022","journal-title":"J. Phys. Conf. Ser."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"5928","DOI":"10.1038\/s41598-022-09932-0","article-title":"High performance recycled CFRP composites based on reused carbon fabrics through sustainable mild solvolysis route","volume":"12","author":"Ballout","year":"2022","journal-title":"Sci. Rep."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Protsenko, A.E., Protsenko, A.N., Shakirova, O.G., and Petrov, V.V. (2023). Recycling of epoxy\/fiberglass composite using supercritical ethanol with (2,3,5-triphenyltetrazolium)2[CuCl4] complex. Polymers, 15.","DOI":"10.3390\/polym15061559"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"9270","DOI":"10.1038\/s41598-023-36183-4","article-title":"Recycling of both resin and fibre from wind turbine blade waste via small molecule-assisted dissolution","volume":"13","author":"Muzyka","year":"2023","journal-title":"Sci. Rep."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"9644","DOI":"10.1039\/D3GC03479H","article-title":"Recycling and recovery of fiber-reinforced polymer composites for end-of-life wind turbine blade management","volume":"25","author":"Shen","year":"2023","journal-title":"Green Chem."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"110435","DOI":"10.1016\/j.compositesb.2022.110435","article-title":"Recycling glass fibers from thermoset epoxy composites by in situ oxonium-type polyionic liquid formation and naphthalene-containing superplasticizer synthesis with the degradation solution of the epoxy resin","volume":"254","author":"Zhao","year":"2023","journal-title":"Compos. 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Energies, 16.","DOI":"10.3390\/en16227624"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"114690","DOI":"10.1016\/j.rser.2024.114690","article-title":"Recovering glass fibers from waste wind turbine blades: Recycling methods, fiber properties, and potential utilization","volume":"202","author":"Xu","year":"2024","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"111290","DOI":"10.1016\/j.compositesb.2024.111290","article-title":"End-of-Life wind turbine blades: Review on recycling strategies","volume":"275","author":"Spini","year":"2024","journal-title":"Compos. Part B Eng."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Nogaki, S., Ito, L., Nakakubo, T., and Tokai, A. (2024). CO2 emissions from blade waste treatments under wind power scenario in Japan from 2021 to 2100. Sustainability, 16.","DOI":"10.3390\/su16052165"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2302150","DOI":"10.1002\/adem.202302150","article-title":"Modeling the solvolysis of composite materials of wind turbine blades","volume":"26","author":"Chen","year":"2024","journal-title":"Adv. Eng. Mater."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Protsenko, A.E. (2024). Recycling of Carbon Fiber Reinforced Plastic with Supercritical Ethanol in the Presence of Sn, Cu, Co Salts. Proceedings of the 2023 the 6th International Conference on Mechanical Engineering and Applied Composite Materials, Sanya, China, 28\u201329 December 2023, Springer Nature.","DOI":"10.1007\/978-981-97-1678-4_20"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.ref.2023.02.001","article-title":"Recycling of wind turbine blades through modern recycling technologies: A road to zero waste","volume":"44","author":"Khalid","year":"2023","journal-title":"Renew. Energy Focus"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Tayebi, S.T., Sambucci, M., and Valente, M. (2024). Waste management of wind turbine blades: A comprehensive review on available recycling technologies with a focus on overcoming potential environmental hazards caused by microplastic production. Sustainability, 16.","DOI":"10.3390\/su16114517"},{"key":"ref_23","first-page":"17","article-title":"State-of-the-art circular economy practices for end-of-life wind turbine blades for use in the construction industry","volume":"47","author":"Tyurkay","year":"2024","journal-title":"Sustain. Prod. Consum."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"108008","DOI":"10.1016\/j.resconrec.2024.108008","article-title":"End-of-life wind turbine blade management across energy transition: A life cycle analysis","volume":"213","author":"Alavi","year":"2025","journal-title":"Resour. Conserv. Recycl."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"115418","DOI":"10.1016\/j.rser.2025.115418","article-title":"End-of-life wind turbine blades and paths to a circular economy","volume":"212","author":"Deeney","year":"2025","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"100710","DOI":"10.1016\/j.dibe.2025.100710","article-title":"Mechanical recycling of GFRP wind turbine blades: Evaluating the sustainability and economic potential of recycled fibers","volume":"23","author":"Menna","year":"2025","journal-title":"Dev. Built Environ."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Buli\u0144ska, S., Sujak, A., and Pyzalski, M. (2024). From waste to renewables: Challenges and opportunities in recycling glass fibre composite products from wind turbine blades for sustainable cement production. Sustainability, 16.","DOI":"10.3390\/su16125150"}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/19\/16\/3428\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T08:18:31Z","timestamp":1786609111000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/19\/16\/3428"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,13]]},"references-count":27,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["ma19163428"],"URL":"https:\/\/doi.org\/10.3390\/ma19163428","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,13]]}}}