{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T03:26:54Z","timestamp":1792121214377,"version":"4.4.0"},"reference-count":50,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,6]],"date-time":"2025-06-06T00:00:00Z","timestamp":1749168000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Agencia Nacional de Investigaci\u00f3n e Innovaci\u00f3n, ANII, Uruguay","award":["FMV_3_2016_1_125956"],"award-info":[{"award-number":["FMV_3_2016_1_125956"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Alkaline treatment is well suited for extracting high-molecular-weight hemicelluloses, specifically hardwoods xylans, which, due to their polymer structure and chemical characteristics, enable the production of films with desirable mechanical, barrier, and optical properties for packaging applications. Despite its relevance, the optimization of antisolvent addition has received little attention in the literature. This study explores the use of eucalyptus industrial residue as feedstock, utilizing a statistical design to determine the optimal extraction conditions for hemicelluloses while minimizing the lignin content in the recovered liquor. The process uses alkali loads that are compatible with those in conventional Kraft pulp mills. Optimal extraction conditions involve a temperature of 105 \u00b0C, 16.7% NaOH charge, and 45 min at maximum temperature. The resulting liquor was subjected to ethanol precipitation under varying pH conditions (initial pH, 9, 7, 5, and 2) and different ethanol-to-liquor ratios (1:1 to 4:1). The acidification was performed using hydrochloric, sulfuric, and acetic acids. Ethanol served as the main antisolvent, while isopropyl alcohol and dioxane were tested for comparison. Results show that 2.3 \u00b1 0.2% of xylans (based on oven-dry biomass) could be extracted, minimizing lignin content in the liquor. This value corresponds to the extraction of 15.6% of the xylans present in the raw material. The highest xylan precipitation yield (78%) was obtained at pH 7, using hydrochloric acid for pH adjustment and an ethanol-to-liquor ratio of 1:1. These findings provide valuable insight into optimizing hemicellulose recovery through antisolvent precipitation, contributing to more efficient biomass valorization strategies within lignocellulosic biorefineries.<\/jats:p>","DOI":"10.3390\/polym17121589","type":"journal-article","created":{"date-parts":[[2025,6,6]],"date-time":"2025-06-06T09:02:03Z","timestamp":1749200523000},"page":"1589","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Alkaline Extraction and Ethanol Precipitation of High-Molecular-Weight Xylan Compounds from Eucalyptus Residues"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2501-9790","authenticated-orcid":false,"given":"Mar\u00eda Noel","family":"Cabrera","sequence":"first","affiliation":[{"name":"Engineering School, Chemical Engineering Institute\/Forest Processes Engineering Group, Universidad de la Rep\u00fablica, Montevideo 11300, Uruguay"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonella","family":"Rossi","sequence":"additional","affiliation":[{"name":"Engineering School, Chemical Engineering Institute\/Forest Processes Engineering Group, Universidad de la Rep\u00fablica, Montevideo 11300, Uruguay"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Ignacio","family":"Guarino","sequence":"additional","affiliation":[{"name":"Engineering School, Chemical Engineering Institute\/Forest Processes Engineering Group, Universidad de la Rep\u00fablica, Montevideo 11300, Uruguay"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6371-310X","authenticated-orcid":false,"given":"Fernando Esteban","family":"Felissia","sequence":"additional","affiliation":[{"name":"Institute of Materials of Misiones, Pulp and Paper Program (PROCYP), Universidad Nacional de Misiones, Posadas 3300, Misiones, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2227-5131","authenticated-orcid":false,"given":"Mar\u00eda Cristina","family":"Area","sequence":"additional","affiliation":[{"name":"Institute of Materials of Misiones, Pulp and Paper Program (PROCYP), Universidad Nacional de Misiones, Posadas 3300, Misiones, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"91","DOI":"10.3390\/cleantechnol2010007","article-title":"Lignocellulosic Biomass Mild Alkaline Fractionation and Resulting Extract Purification Processes: Conditions, Yields, and Purities","volume":"2","author":"Oriez","year":"2020","journal-title":"Clean. 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