{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T06:08:22Z","timestamp":1761890902255,"version":"build-2065373602"},"reference-count":56,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,10,30]],"date-time":"2025-10-30T00:00:00Z","timestamp":1761782400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Processes"],"abstract":"<jats:p>Advancing circular bioeconomy in thermochemical biorefineries requires species-specific data that link biomass composition and thermochemical performance. Here, we provide the first integrated thermochemical dataset for Quercus pubescens bark combining FT-IR, XRD, XRF, TGA, and measured ash fusion temperatures (AFT). The results reveal that bark is enriched in phenolic extractives (21.2%) and inorganics (15%), with calcium oxalate monohydrate (COM) dominating the inorganic fraction, as confirmed by FT-IR and XRD. Thermal decomposition occurs between 150 \u00b0C and 690 \u00b0C. Pyrolysis follows diffusion-controlled kinetics, with apparent activation energies for bark and its fractions ranging between 70 and 103 kJ mol\u22121. Extraction increases the activation energy of bark. The ash exhibits a high AFT (softening: 1421 \u00b0C, flow: 1467 \u00b0C), placing this feedstock within the low-slagging, moderate-fouling range compared to other lignocellulosics. The observed COM-to-CaCO3\/CaO transformation upon heating contributes to the elevated AFT. Reactivity analyses of bark fractions support thermochemical biorefinery routing of fractions: extracted bark (EB) and desuberinised bark (DB) are highly reactive and well-suited to combustion\/gasification, whereas raw bark (B) and Klason lignin (KL) exhibit higher thermal stability and yield more persistent char, favoring slow pyrolysis for biochar production. Such routing strategies optimize energy recovery and also enable co-products with environmental co-benefits.<\/jats:p>","DOI":"10.3390\/pr13113484","type":"journal-article","created":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T03:33:07Z","timestamp":1761881587000},"page":"3484","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Chemical Composition and Reactivity of Quercus pubescens Bark and Bark Fractions for Thermochemical Biorefinery Applications"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3734-466X","authenticated-orcid":false,"given":"Umut","family":"\u015een","sequence":"first","affiliation":[{"name":"Department of Energy Systems Engineering, Izmir Institute of Technology, 35430 G\u00fclbahce, Turkey"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-3970-7479","authenticated-orcid":false,"given":"B\u00fc\u015fra","family":"Balc\u0131","sequence":"additional","affiliation":[{"name":"Department of Energy Systems Engineering, Izmir Institute of Technology, 35430 G\u00fclbahce, Turkey"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6689-7920","authenticated-orcid":false,"given":"\u0218efik","family":"Ar\u0131c\u0131","sequence":"additional","affiliation":[{"name":"Biomass Energy Systems and Technologies Application and Research Center, Ege University, 35100 Bornova, Turkey"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2579-8349","authenticated-orcid":false,"given":"Beyza","family":"\u015eat","sequence":"additional","affiliation":[{"name":"Department of Interior Architecture and Environmental Design, Faculty of Architecture and Design, \u00d6zye\u011fin University, 34794 Istanbul, Turkey"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0280-5219","authenticated-orcid":false,"given":"Isabel","family":"Miranda","sequence":"additional","affiliation":[{"name":"Centro de Estudos Florestais, Laborat\u00f3rio Associado Terra, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5393-4443","authenticated-orcid":false,"given":"Helena","family":"Pereira","sequence":"additional","affiliation":[{"name":"Centro de Estudos Florestais, Laborat\u00f3rio Associado Terra, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,30]]},"reference":[{"key":"ref_1","unstructured":"Yalt\u0131r\u0131k, F. 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