{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T22:37:33Z","timestamp":1788475053929,"version":"build-2803163510"},"reference-count":47,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2024,8,29]],"date-time":"2024-08-29T00:00:00Z","timestamp":1724889600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004442","name":"National Science Centre","doi-asserted-by":"publisher","award":["2019\/33\/B\/ST8\/02044"],"award-info":[{"award-number":["2019\/33\/B\/ST8\/02044"]}],"id":[{"id":"10.13039\/501100004442","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The adsorption properties of microporous carbon materials modified with iron citrate were investigated. The carbon materials were produced based on resorcinol-formaldehyde resin, treated in a microwave assisted solvothermal reactor, and next carbonized in the tube furnace at a temperature of 700 \u00b0C under argon atmosphere. Iron citrate was applied as a modifier, added to the material precursor before the synthesis in the reactor, in the quantity enabling to obtain the nanocomposites with C:Fe mass ratio equal to 10:1. Some samples were additionally activated using potassium oxalate or potassium hydroxide. The phase composition of the produced nanocomposites was determined using the X-ray diffraction method. Scanning and transmission electron microscopy was applied to characterize the changes in samples\u2019 morphology resulting from the activation process and\/or the introduction of iron into the carbon matrix. The adsorption of nitrogen from gas phase and dyes (methylene blue and congo red) from water solution on the obtained materials was investigated. In the case of methylene blue, the adsorption equilibrium isotherms followed the Langmuir isotherm model. However, in the case of congo red, a linear dependency of adsorption and concentration in a broad equilibrium concentration range was found and well-described using the Henry equation. The most efficient adsorption of methylene blue was noticed for the sample activated with potassium hydroxide and modified with iron citrate, and a maximum adsorption capacity of 696 mg\/g was achieved. The highest congo red adsorption was noticed for the non-activated sample modified with iron citrate, and the partition coefficient for this material equaled 171 dm3\/g.<\/jats:p>","DOI":"10.3390\/molecules29174090","type":"journal-article","created":{"date-parts":[[2024,8,29]],"date-time":"2024-08-29T03:40:39Z","timestamp":1724902839000},"page":"4090","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Activated Iron-Porous Carbon Nanomaterials as Adsorbents for Methylene Blue and Congo Red"],"prefix":"10.3390","volume":"29","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7542-8093","authenticated-orcid":false,"given":"Daniel","family":"Sibera","sequence":"first","affiliation":[{"name":"Department of General Civil Engineering, Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, al. Piast\u00f3w 50a, 70-311 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9878-2340","authenticated-orcid":false,"given":"Iwona","family":"Pe\u0142ech","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego,10, 70-322 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2160-5431","authenticated-orcid":false,"given":"Piotr","family":"Staciwa","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego,10, 70-322 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8461-7707","authenticated-orcid":false,"given":"Robert","family":"Pe\u0142ech","sequence":"additional","affiliation":[{"name":"Department of Chemical Organic Technology and Polymeric Materials, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego 10, 70-322 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8403-2119","authenticated-orcid":false,"given":"Ewa","family":"Ekiert","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego,10, 70-322 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2788-7097","authenticated-orcid":false,"given":"Gulsen Yagmur","family":"Kayalar","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Engineering, Eski\u015fehir Technical University, 26555 Eski\u015fehir, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2443-1510","authenticated-orcid":false,"given":"Urszula","family":"Narkiewicz","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego,10, 70-322 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"499","DOI":"10.1007\/s11270-010-0663-y","article-title":"Equilibrium, Kinetics and Mechanism of Removal of Methylene Blue from Aqueous Solution by Adsorption onto Pine Cone Biomass of Pinus radiata","volume":"218","author":"Sen","year":"2011","journal-title":"Water Air Soil. 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