{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T01:29:29Z","timestamp":1771550969103,"version":"3.50.1"},"reference-count":57,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T00:00:00Z","timestamp":1753315200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\u2014Foundation for Science and Technology, I.P.","award":["UIDB\/00681"],"award-info":[{"award-number":["UIDB\/00681"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Olive tree branches (OB) and leaves (OL) from the Viseu region (Portugal) were studied for their chemical composition and liquefaction behavior using polyalcohols. Chemical analysis revealed that OL contained higher ash content (4.08%) and extractives, indicating more bioactive compounds, while OB had greater \u03b1-cellulose (30.47%) and hemicellulose (27.88%). Lignin content was higher in OL (21.64%) than OB (16.40%). Liquefaction experiments showed that increasing the temperature from 140 \u00b0C to 180 \u00b0C improved conversion, with OB showing a larger increase (52.5% to 80.9%) compared to OL (66% to 72%). OB reached peak conversion faster, and the optimal particle size for OB was 40\u201360 mesh, while OL performed better at finer sizes. OL benefited more from higher solvent ratios, whereas OB achieved high conversion with less solvent. FTIR analysis confirmed that acid-catalyzed liquefaction breaks down lignocellulosic structures, depolymerizes cellulose and hemicellulose, and modifies lignin, forming hydroxyl, aliphatic, and carbonyl groups. These changes reflect progressive biomass degradation and the incorporation of polyalcohol components, converting solid biomass into a reactive, polyol-rich liquid. The study highlights the distinct chemical and processing characteristics of olive branches and leaves, informing their potential industrial applications.<\/jats:p>","DOI":"10.3390\/su17156739","type":"journal-article","created":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T11:58:53Z","timestamp":1753358333000},"page":"6739","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Olive Tree (Olea europaea) Pruning: Chemical Composition and Valorization of Wastes Through Liquefaction"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4308-1563","authenticated-orcid":false,"given":"Idalina","family":"Domingos","sequence":"first","affiliation":[{"name":"Centre for Natural Resources, Technology and Management School, Polytechnic University of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9290-2686","authenticated-orcid":false,"given":"Miguel","family":"Ferreira","sequence":"additional","affiliation":[{"name":"IT Department, Technology and Management School, Polytechnic University of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7596-8065","authenticated-orcid":false,"given":"Jos\u00e9","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Centre for Natural Resources, Technology and Management School, Polytechnic University of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6660-3128","authenticated-orcid":false,"given":"Bruno","family":"Esteves","sequence":"additional","affiliation":[{"name":"Centre for Natural Resources, Technology and Management School, Polytechnic University of Viseu, Av. Cor. Jos\u00e9 Maria Vale de Andrade, 3504-510 Viseu, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Espeso, J., Isaza, A., Lee, J.Y., S\u00f6rensen, P.M., Jurado, P., Avena-Bustillos, R.D.J., Olaizola, M., and Arboleya, J.C. (2021). Olive Leaf Waste Management. Front. Sustain. Food Syst., 5.","DOI":"10.3389\/fsufs.2021.660582"},{"key":"ref_2","unstructured":"(2025, April 22). International Olive Council. Available online: https:\/\/www.internationaloliveoil.org\/wp-content\/uploads\/2023\/12\/HO-CE901-13-12-2023-P.pdf."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Ram\u00edrez, E.M., Brenes, M., Romero, C., and Medina, E. (2022). Chemical and Enzymatic Characterization of Leaves from Spanish Table Olive Cultivars. 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