{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T11:21:45Z","timestamp":1774264905362,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,5,11]],"date-time":"2020-05-11T00:00:00Z","timestamp":1589155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT Grants PEst\u2010OE\/QUI\/UI0619\/2011","award":["Grants PEst\u2010OE\/QUI\/UI0619\/2011"],"award-info":[{"award-number":["Grants PEst\u2010OE\/QUI\/UI0619\/2011"]}]},{"DOI":"10.13039\/501100001871","name":"FCT","doi-asserted-by":"publisher","award":["SFRH\/BD\/82696\/2011"],"award-info":[{"award-number":["SFRH\/BD\/82696\/2011"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National (OE) and European Union (FEDER, program COMPETE of QREN) funds","award":["COMPETE of QREN"],"award-info":[{"award-number":["COMPETE of QREN"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The aim of this work was to test activated carbons derived from hydrochars produced from sunflower stem, olive stone and walnut shells, as adsorbents for emerging contaminants in aqueous solution, namely fluoxetine and nicotinic acid. The adsorption capacity was determined by the chemical nature of the adsorbents, namely the presence of specific functional groups and their positive or negative ionization in aqueous solutions and also by steric factors. The activated carbons produced by air showed a higher adsorption capacity of fluoxetine, whilst the samples produced by carbon dioxide activation were more useful to remove nicotinic acid. In general, surface acidity was advantageous for fluoxetine adsorption and detrimental for nicotinic acid removal. The adsorption mechanisms involved in each case were discussed and related to the adsorbents characteristics. The maximum adsorption capacity, Q0, given by the Langmuir model was 44.1 and 91.9 mg g\u22121 for fluoxetine and nicotinic acid adsorption, respectively.<\/jats:p>","DOI":"10.3390\/molecules25092264","type":"journal-article","created":{"date-parts":[[2020,5,12]],"date-time":"2020-05-12T02:41:20Z","timestamp":1589251280000},"page":"2264","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Surface Interactions during the Removal of Emerging Contaminants by Hydrochar-Based Adsorbents"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8851-2710","authenticated-orcid":false,"given":"Silvia","family":"Rom\u00e1n","sequence":"first","affiliation":[{"name":"Departmento de F\u00edsica Aplicada, Universidad de Extremadura, Avda. Elvas s\/n, CP: 06006 Badajoz, Spain"}]},{"given":"Jo\u00e2o Manuel","family":"Valente Nabais","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Escola de Ci\u00eancias e Tecnologia, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Center (CHRC), NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas Campo M\u00e1rtires da P\u00e1tria, 130, 1169-056 Lisboa, Portugal"}]},{"given":"Beatriz","family":"Ledesma","sequence":"additional","affiliation":[{"name":"Departmento de F\u00edsica Aplicada, Universidad de Extremadura, Avda. Elvas s\/n, CP: 06006 Badajoz, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8782-0313","authenticated-orcid":false,"given":"Carlos","family":"Laginhas","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Escola de Ci\u00eancias e Tecnologia, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"}]},{"given":"Maria-Magdalena","family":"Titirici","sequence":"additional","affiliation":[{"name":"Materials Research Institute, Queen Mary University London, Mile End Road, London E14NS, UK"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"160","DOI":"10.1002\/bbb.198","article-title":"Hydrothermal carbonization of biomass: A summary and discussion of chemical mechanisms for process engineering","volume":"4","author":"Funke","year":"2010","journal-title":"Biofuel. Bioprod. 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