{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:42:08Z","timestamp":1785436928195,"version":"3.56.0"},"reference-count":45,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2026,5,31]],"date-time":"2026-05-31T00:00:00Z","timestamp":1780185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42407370"],"award-info":[{"award-number":["42407370"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["42407370"],"award-info":[{"award-number":["42407370"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Changsha University of Science and Technology Graduate Student Scientific Research and Innovation Project","award":["CLKYCX24053"],"award-info":[{"award-number":["CLKYCX24053"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Flue gas torrefaction is an emerging biomass pretreatment technology that utilizes industrial flue gas as a reactive medium to replace inert atmospheres. However, the intrinsic complexity of biomass and the catalytic interference of ash hinder mechanistic elucidation. This study investigated the torrefaction behavior of demineralized poplar wood under N2, CO2, dry flue gas (DFG), and wet flue gas (WFG) at 300 \u00b0C for 5\u201320 min. Thermogravimetric analysis combined with kinetic modeling (FWO, KAS, and CR methods) revealed that the apparent activation energy (E\u03b1) varied non-monotonically with atmosphere oxidizability. Under N2, the average E\u03b1 was 177 kJ\/mol following the three-dimensional diffusion model (D5). CO2 gave the highest average E\u03b1 (314 kJ\/mol) with the Avrami\u2013Erofeev nucleation model (A1\/4). DFG and WFG significantly reduced the average E\u03b1 to 133 and 128 kJ\/mol, respectively, both following the A1\/3 model. Consistently, WFG yields the lowest char and the highest gas yield. XPS and FTIR analyses indicated that flue gas atmospheres, especially WFG, promoted deeper deoxygenation and aromatization of biochar. Tar composition underwent a noticeable transition from ketones to aldehydes and saccharides under flue gas conditions, with the most remarkable variation observed under WFG. Gaseous products were dominated by CO2 under N2 and by CO under CO2, while DFG and WFG produced moderate and stable gas compositions. These findings demonstrate that flue gas torrefaction, particularly under WFG, effectively enhances biomass effectively upgrades biomass quality by regulating pyrolysis kinetics and product distribution, and demineralized biomass is a suitable intermediate model for mechanistic investigation.<\/jats:p>","DOI":"10.3390\/polym18111370","type":"journal-article","created":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T08:09:16Z","timestamp":1780301356000},"page":"1370","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Torrefaction of Demineralized Wood with Flue Gas: Kinetics, Product Distribution, and Thermal Conversion"],"prefix":"10.3390","volume":"18","author":[{"given":"Xiaoyu","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Energy and Power Engineering, Changsha University of Science & Technology, Changsha 410114, China"},{"name":"Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences (CAS), Nengyuan Road, Guangzhou 510640, China"},{"name":"Guangdong Provincial Key Laboratory of High-Quality Recycling of End-of-Life New Energy Devices, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingkun","family":"Han","sequence":"additional","affiliation":[{"name":"Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences (CAS), Nengyuan Road, Guangzhou 510640, China"},{"name":"Guangdong Provincial Key Laboratory of High-Quality Recycling of End-of-Life New Energy Devices, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shan","family":"Cheng","sequence":"additional","affiliation":[{"name":"College of Energy and Power Engineering, Changsha University of Science & Technology, Changsha 410114, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Tian","sequence":"additional","affiliation":[{"name":"College of Energy and Power Engineering, Changsha University of Science & Technology, Changsha 410114, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0291-3263","authenticated-orcid":false,"given":"Jing","family":"Gu","sequence":"additional","affiliation":[{"name":"Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences (CAS), Nengyuan Road, Guangzhou 510640, China"},{"name":"Guangdong Provincial Key Laboratory of High-Quality Recycling of End-of-Life New Energy Devices, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoteng","family":"Jiang","sequence":"additional","affiliation":[{"name":"Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences (CAS), Nengyuan Road, Guangzhou 510640, China"},{"name":"Guangdong Provincial Key Laboratory of High-Quality Recycling of End-of-Life New Energy Devices, Guangzhou 510640, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"123468","DOI":"10.1016\/j.jhazmat.2020.123468","article-title":"Combustion Performance and Emissions from Torrefied and Water Washed Biomass Using a Kg-Scale Burner","volume":"402","author":"Chen","year":"2020","journal-title":"J. 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