{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T12:08:57Z","timestamp":1785845337661,"version":"3.56.0"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,21]],"date-time":"2025-05-21T00:00:00Z","timestamp":1747785600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council","doi-asserted-by":"publisher","award":["NFFRG-2020-00117"],"award-info":[{"award-number":["NFFRG-2020-00117"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council","doi-asserted-by":"publisher","award":["2022-FNFR-310130"],"award-info":[{"award-number":["2022-FNFR-310130"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003151","name":"Fonds de Recherche du Qu\u00e9bec \u2013 Nature et Technologies","doi-asserted-by":"publisher","award":["NFFRG-2020-00117"],"award-info":[{"award-number":["NFFRG-2020-00117"]}],"id":[{"id":"10.13039\/501100003151","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003151","name":"Fonds de Recherche du Qu\u00e9bec \u2013 Nature et Technologies","doi-asserted-by":"publisher","award":["2022-FNFR-310130"],"award-info":[{"award-number":["2022-FNFR-310130"]}],"id":[{"id":"10.13039\/501100003151","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Addressing the removal of hazardous phenolic pollutants from water, this study introduces an eco-friendly adsorbent composed of waste-derived hydrochar immobilized in alginate beads (Alg\/HC). The physicochemical properties of the Alg\/HC beads were characterized using SEM, XRD, and FTIR, confirming hydrochar encapsulation and partial structural preservation. Batch studies revealed a maximum 2-nitrophenol (2-NP) adsorption capacity of 15.80 \u00b1 0.62 mg\/g at 30 mg\/L of 2-NP, with kinetics best described by the Elovich and pseudo-second-order models. Freundlich isotherm fitting indicated multilayer adsorption on heterogeneous surfaces, likely governed by hydrogen bonding and \u03c0\u2013\u03c0 interactions. In a fixed-bed column system, Alg\/HC beads demonstrated a continuous adsorption capacity of 6.84 \u00b1 0.45 mg\/g at 10 mg\/L of 2-NP, with breakthrough behavior modeled by the Yoon\u2013Nelson and Thomas equations. The beads maintained stable performance across four regeneration cycles using a mild water\/ethanol desorption method. This work represents the first study to explore Alg\/HC composites for 2-NP removal in both batch and continuous modes, demonstrating their potential as low-cost, regenerable adsorbents for tertiary treatment of phenolic industrial wastewater.<\/jats:p>","DOI":"10.3390\/ma18102412","type":"journal-article","created":{"date-parts":[[2025,5,21]],"date-time":"2025-05-21T13:59:43Z","timestamp":1747835983000},"page":"2412","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Sustainable Alginate\u2013Hydrochar Composite Beads for 2-Nitrophenol Adsorption in Batch and Fixed-Bed Systems"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4474-8718","authenticated-orcid":false,"given":"Dalia","family":"Allouss","sequence":"first","affiliation":[{"name":"Group of Research on Technologies and Processes, Department of Chemical and Biotechnological Engineering, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9764-4042","authenticated-orcid":false,"given":"Nicolas","family":"Abatzoglou","sequence":"additional","affiliation":[{"name":"Group of Research on Technologies and Processes, Department of Chemical and Biotechnological Engineering, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8017-7946","authenticated-orcid":false,"given":"In\u00e8s Esma","family":"Achouri","sequence":"additional","affiliation":[{"name":"Group of Research on Technologies and Processes, Department of Chemical and Biotechnological Engineering, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"},{"name":"Canada Research Chair on Process Intensification for Advanced Catalyst and Sustainable Energy, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"50799","DOI":"10.1007\/s11356-021-14335-1","article-title":"Selenium Speciation and Bioavailability from Mine Discharge to the Environment: A Field Study in Northern Quebec, Canada","volume":"28","author":"Etteieb","year":"2021","journal-title":"Environ. 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