{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T21:41:28Z","timestamp":1791582088485,"version":"4.3.4"},"reference-count":91,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,1,22]],"date-time":"2025-01-22T00:00:00Z","timestamp":1737504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Biodiesel produced via oil transesterification often contains metallic impurities, such as copper, which affects its quality and engine performance. This study explores the use of activated carbon prepared from spent coffee grounds to remove copper from biodiesel. Activated carbon samples were prepared via biomass pyrolysis and chemical activation with KOH and HNO3. The optimal conditions for copper adsorption were determined using a Taguchi L9 design. Maximum adsorption capacities were 13.4 and 17.3 mg\/g at 30 and 40 \u00b0C, respectively, in batch adsorbers. In packed-bed columns, the axial dispersion reduced the adsorption efficiency obtaining bed adsorption capacities from 1.9 to 5.1 mg\/g under tested experimental conditions. Adsorbent characterization and adsorption modeling indicated that copper removal was driven by multi-cationic interactions, where carboxylic groups from carbon surface acted as key active sites. The new adsorbent outperformed commercial bone char, making it a cost-effective alternative to improve biodiesel production contributing to the energy matrix diversification.<\/jats:p>","DOI":"10.3390\/molecules30030483","type":"journal-article","created":{"date-parts":[[2025,1,22]],"date-time":"2025-01-22T09:52:20Z","timestamp":1737539540000},"page":"483","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Purification of Biodiesel Polluted by Copper Using an Activated Carbon Prepared from Spent Coffee Grounds: Adsorption Property Tailoring, Batch and Packed-Bed Studies"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-8043-2363","authenticated-orcid":false,"given":"Daniel Eduardo","family":"C\u00e1rdenas-Pi\u00f1eros","sequence":"first","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico-Instituto Tecnol\u00f3gico de Aguascalientes, Aguascalientes 20256, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4102-2252","authenticated-orcid":false,"given":"Hilda Elizabeth","family":"Reynel-\u00c1vila","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico-Instituto Tecnol\u00f3gico de Aguascalientes, Aguascalientes 20256, Mexico"},{"name":"CONAHCYT\u2014Consejo Nacional de Humanidades, Ciencias y Tecnolog\u00edas, Ciudad de M\u00e9xico 03940, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lizbeth Liliana","family":"D\u00edaz-Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico-Instituto Tecnol\u00f3gico de Aguascalientes, Aguascalientes 20256, Mexico"},{"name":"Facultad de Ciencias Qu\u00edmicas, Universidad Aut\u00f3noma de Nuevo Le\u00f3n, Nuevo Le\u00f3n 66455, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0197-3539","authenticated-orcid":false,"given":"Adri\u00e1n","family":"Bonilla-Petriciolet","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico-Instituto Tecnol\u00f3gico de Aguascalientes, Aguascalientes 20256, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2507-4650","authenticated-orcid":false,"given":"Carlos Javier","family":"Dur\u00e1n-Valle","sequence":"additional","affiliation":[{"name":"IACYS\u2014Instituto del Agua, Cambio Clim\u00e1tico y Sostenibilidad, Universidad de Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3744-5172","authenticated-orcid":false,"given":"Marta","family":"Adame-Pereira","sequence":"additional","affiliation":[{"name":"IACYS\u2014Instituto del Agua, Cambio Clim\u00e1tico y Sostenibilidad, Universidad de Extremadura, 06006 Badajoz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8450","DOI":"10.1016\/j.ijhydene.2016.11.125","article-title":"Biofuel production: Challenges and opportunities","volume":"42","author":"Rodionova","year":"2017","journal-title":"Int. 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