{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T22:18:15Z","timestamp":1788387495716,"version":"build-2803163510"},"reference-count":77,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,7,30]],"date-time":"2023-07-30T00:00:00Z","timestamp":1690675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Mexican Institute of Water Technology","award":["DP2101.1"],"award-info":[{"award-number":["DP2101.1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Inorganic arsenic in drinking water from groundwater sources is one of the potential causes of arsenic-contaminated environments, and it is highly toxic to human health even at low concentrations. The purpose of this study was to develop a magnetic adsorbent capable of removing arsenic from water. Fe3O4-monolithic resorcinol-formaldehyde carbon xerogels are a type of porous material that forms when resorcinol and formaldehyde (RF) react to form a polymer network, which is then cross-linked with magnetite. Sonication-assisted direct and indirect methods were investigated for loading Fe3O4 and achieving optimal mixing and dispersion of Fe3O4 in the RF solution. Variations of the molar ratios of the catalyst (R\/C = 50, 100, 150, and 200), water (R\/W = 0.04 and 0.05), and Fe3O4 (M\/R = 0.01, 0.03, 0.05, 0.1, 0.15, and 0.2), and thermal treatment were applied to evaluate their textural properties and adsorption capacities. Magnetic carbon xerogel monoliths (MXRF600) using indirect sonication were pyrolyzed at 600 \u00b0C for 6 h with a nitrogen gas flow in the tube furnace. Nanoporous carbon xerogels with a high surface area (292 m2\/g) and magnetic properties were obtained. The maximum monolayer adsorption capacity of As(III) and As(V) was 694.3 \u00b5g\/g and 1720.3 \u00b5g\/g, respectively. The incorporation of magnetite in the xerogel structure was physical, without participation in the polycondensation reaction, as confirmed by XRD, FTIR, and SEM analysis. Therefore, Fe3O4-monolithic resorcinol-formaldehyde carbon xerogels were developed as a potential adsorbent for the effective removal of arsenic with low and high ranges of As(III) and As(V) concentrations from groundwater.<\/jats:p>","DOI":"10.3390\/gels9080618","type":"journal-article","created":{"date-parts":[[2023,7,31]],"date-time":"2023-07-31T02:13:32Z","timestamp":1690769612000},"page":"618","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["The Development of Fe3O4-Monolithic Resorcinol-Formaldehyde Carbon Xerogels Using Ultrasonic-Assisted Synthesis for Arsenic Removal of Drinking Water"],"prefix":"10.3390","volume":"9","author":[{"given":"Sasirot","family":"Khamkure","sequence":"first","affiliation":[{"name":"Postgraduate Department, CONAHCYT-Mexican Institute of Water Technology, Jiutepec 62550, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6733-2032","authenticated-orcid":false,"given":"Pr\u00f3coro","family":"Gamero-Melo","sequence":"additional","affiliation":[{"name":"Sustainability of Natural Resources and Energy, Cinvestav Saltillo, Ramos Arizpe 25900, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1219-7579","authenticated-orcid":false,"given":"Sof\u00eda Esperanza","family":"Garrido-Hoyos","sequence":"additional","affiliation":[{"name":"Postgraduate Department, Mexican Institute of Water Technology, Jiutepec 62550, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audberto","family":"Reyes-Rosas","sequence":"additional","affiliation":[{"name":"Department of Bioscience and Agrotechnology, Research Center of Applied Chemistry, Saltillo 25294, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3412-7459","authenticated-orcid":false,"given":"Daniella-Esperanza","family":"Pacheco-Catal\u00e1n","sequence":"additional","affiliation":[{"name":"Renewable Energy Unit, Yucatan Scientific Research Center, Merida 97302, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arely Monserrat","family":"L\u00f3pez-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Sustainability of Natural Resources and Energy, Cinvestav Saltillo, Ramos Arizpe 25900, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,30]]},"reference":[{"key":"ref_1","unstructured":"Agency for Toxic Substances and Disease Registry (ATSDR) (2007). Toxicological Profile for Arsenic. Atlanta, 1\u2013559."},{"key":"ref_2","unstructured":"(2002). Environmental Protection Agency (EPA) National Primary Drinking Water Regulations: Long Term 1 Enhanced Surface Water Treatment Rule. Fed. Regist., 75, 1812\u20131844."},{"key":"ref_3","unstructured":"WHO (2022). Guidelines for Drinking-Water Quality: Fourth Edition Incorporating the First and Second Addenda, WHO."},{"key":"ref_4","unstructured":"Secretary of Health (SSA) (2021). Official Mexican Standards NOM-127-SSA1-2021, Environmental Health, Water for Human Use and Consumption\u2014Permissible Limits of Quality and Treatments to Which Water Must Be Submitted for Its Drinkability, Official Daily of the Federation."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1080\/19438150903185077","article-title":"Contamination of groundwater by arsenic: A review of occurrence, causes, impacts, remedies and membrane-based purification","volume":"6","author":"Pal","year":"2009","journal-title":"J. Integr. Environ. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/j.ecoenv.2014.10.009","article-title":"Arsenic contamination, consequences and remediation techniques: A review","volume":"112","author":"Singh","year":"2015","journal-title":"Ecotoxicol. Environ. Saf."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Shankar, S., and Shanker, U. (2014). Shikha Arsenic contamination of groundwater: A review of sources, prevalence, health risks, and strategies for mitigation. Sci. World J., 2014.","DOI":"10.1155\/2014\/304524"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"257","DOI":"10.29024\/aogh.913","article-title":"Potential co-exposure to arsenic and fluoride and biomonitoring equivalents for Mexican children","volume":"84","author":"Gonsebatt","year":"2018","journal-title":"Ann. Glob. Health"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"4587","DOI":"10.3390\/ijerph120504587","article-title":"A concurrent exposure to arsenic and fluoride from drinking water in Chihuahua, Mexico","volume":"12","author":"Ishida","year":"2015","journal-title":"Int. J. Environ. Res. Public Health"},{"key":"ref_10","first-page":"5","article-title":"Geological differentiation of groundwater threshold concentrations of arsenic, vanadium and fluorine in El Bajio Guanajuatense, Mexico","volume":"55","year":"2016","journal-title":"Geofis. Int."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"34355","DOI":"10.1007\/s11356-021-13070-x","article-title":"Inflammation biomarkers associated with arsenic exposure by drinking water and respiratory outcomes in indigenous children from three Yaqui villages in southern Sonora, M\u00e9xico","volume":"28","author":"Burgess","year":"2021","journal-title":"Environ. Sci. Pollut. Res."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Mart\u00ednez-Acu\u00f1a, M.I., Mercado-Reyes, M., Alegr\u00eda-Torres, J.A., and Mej\u00eda-Saavedra, J.J. (2016). Preliminary human health risk assessment of arsenic and fluoride in tap water from Zacatecas, M\u00e9xico. Environ. Monit. Assess., 188.","DOI":"10.1007\/s10661-016-5453-6"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1080\/09603123.2014.958139","article-title":"The health effects of exposure to arsenic-contaminated drinking water: A review by global geographical distribution","volume":"25","author":"Huang","year":"2015","journal-title":"Int. J. Environ. Health Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1016\/j.envres.2017.01.028","article-title":"Low-level arsenic in drinking water and risk of incident myocardial infarction: A cohort study","volume":"154","author":"Monrad","year":"2017","journal-title":"Environ. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"262","DOI":"10.21149\/11085","article-title":"Arsenic exposure in northern Mexican women","volume":"62","year":"2020","journal-title":"Salud Publica Mex."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Shih, Y.-H., Scannell Bryan, M., and Argos, M. (2020). Association between prenatal arsenic exposure, birth outcomes, and pregnancy complications: An observational study within the National Children\u2019s Study cohort. Environ. Res., 183.","DOI":"10.1016\/j.envres.2020.109182"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Chen, H., Zhang, H., Wang, X., Wu, Y., Zhang, Y., Chen, S., Zhang, W., Sun, X., Zheng, T., and Xia, W. (2023). Prenatal arsenic exposure, arsenic metabolism and neurocognitive development of 2-year-old children in low-arsenic areas. Environ. Int., 174.","DOI":"10.1016\/j.envint.2023.107918"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1007\/s10311-016-0590-2","article-title":"Occurrence and methods to remove arsenic and fluoride contamination in water","volume":"15","author":"Bibi","year":"2017","journal-title":"Environ. Chem. Lett."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/j.eti.2018.12.003","article-title":"Technology alternatives for decontamination of arsenic-rich groundwater\u2014A critical review","volume":"13","author":"Ghosh","year":"2019","journal-title":"Environ. Technol. Innov."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Amiri, S., Vatanpour, V., and He, T. (2022). Optimization of Coagulation-Flocculation Process in Efficient Arsenic Removal from Highly Contaminated Groundwater by Response Surface Methodology. Molecules, 27.","DOI":"10.3390\/molecules27227953"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Rathi, B.S., and Kumar, P.S. (2021). A review on sources, identification and treatment strategies for the removal of toxic Arsenic from water system. J. Hazard. Mater., 418.","DOI":"10.1016\/j.jhazmat.2021.126299"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Abdellaoui, Y., El Ibrahimi, B., Abou Oualid, H., Kassab, Z., Quintal-Franco, C., Gi\u00e1coman-Vallejos, G., and Gamero-Melo, P. (2021). Iron-zirconium microwave-assisted modification of small-pore zeolite W and its alginate composites for enhanced aqueous removal of As(V) ions: Experimental and theoretical studies. Chem. Eng. J., 421.","DOI":"10.1016\/j.cej.2021.129909"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Wang, H., Qi, X., Yan, G., and Shi, J. (2023). Copper-doped ZIF-8 nanomaterials as an adsorbent for the efficient removal of As(V) from wastewater. J. Phys. Chem. Solids, 179.","DOI":"10.1016\/j.jpcs.2023.111408"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Lingamdinne, L.P., Choi, J.S., Choi, Y.L., Chang, Y.Y., and Koduru, J.R. (2023). Stable and recyclable lanthanum hydroxide\u2013doped graphene oxide biopolymer foam for superior aqueous arsenate removal: Insight mechanisms, batch, and column studies. Chemosphere, 313.","DOI":"10.1016\/j.chemosphere.2022.137615"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Fang, Z., Li, Y., Huang, C., and Liu, Q. (2023). Amine functionalization of iron-based metal-organic frameworks MIL-101 for removal of arsenic species: Enhanced adsorption and mechanisms. J. Environ. Chem. Eng., 11.","DOI":"10.1016\/j.jece.2023.110155"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"L\u00f3pez-Mart\u00ednez, A.M., Khamkure, S., and Gamero-Melo, P. (2023). Bifunctional Adsorbents Based on Jarosites for Removal of Inorganic Micropollutants from Water. Separations, 10.","DOI":"10.3390\/separations10050309"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Nguyen, T.H., Nguyen, T.V., Vigneswaran, S., Ha, N.T.H., and Ratnaweera, H. (2023). A Review of Theoretical Knowledge and Practical Applications of Iron-Based Adsorbents for Removing Arsenic from Water. Minerals, 13.","DOI":"10.3390\/min13060741"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"39545","DOI":"10.1039\/C8RA08512A","article-title":"A critical review on arsenic removal from water using iron-based adsorbents","volume":"8","author":"Hao","year":"2018","journal-title":"RSC Adv."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"M\u00eenzatu, V., Davidescu, C.M., Negrea, P., Ciopec, M., Muntean, C., Hulka, I., Paul, C., Negrea, A., and Du\u021beanu, N. (2019). Synthesis, characterization and adsorptive performances of a composite material based on carbon and iron oxide particles. Int. J. Mol. Sci., 20.","DOI":"10.3390\/ijms20071609"},{"key":"ref_30","unstructured":"Fierro, V., Celzard, A., Fierro, V., Szczurek, A., Braghiroli, F., Parmentier, J., Pizzi, A., Suhfxuvruv, S., Fduerq, R.I., and Dqg, D. (2023, April 19). Carbon gels derived from natural resources Geles de carb\u00f3n de origen natural. 2012, 1\u20137. Available online: https:\/\/digital.csic.es\/handle\/10261\/81796."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1007\/s10971-018-4611-4","article-title":"Preparation of SiO2\u2013ZrO2 xerogel and its application for the removal of organic dye","volume":"86","author":"Huang","year":"2018","journal-title":"J. Sol-Gel Sci. Technol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1007\/s10450-018-9933-6","article-title":"Resorcinol\u2013formaldehyde carbon xerogel as selective adsorbent of carbon dioxide present on biogas","volume":"24","author":"Regufe","year":"2018","journal-title":"Adsorption"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1016\/j.micromeso.2015.05.017","article-title":"Hierarchical MOF-xerogel monolith composites from embedding MIL-100(Fe, Cr) and MIL-101(Cr) in resorcinol-formaldehyde xerogels for water adsorption applications","volume":"215","author":"Wickenheisser","year":"2015","journal-title":"Microporous Mesoporous Mater."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"3931","DOI":"10.1021\/acsomega.0c05787","article-title":"Synthesis of an Alginate-Based Fe3O4-MnO2Xerogel and Its Application for the Concurrent Elimination of Cr(VI) and Cd(II) from Aqueous Solution","volume":"6","author":"Kumar","year":"2021","journal-title":"ACS Omega"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Pradhan, S., Hedberg, J., Blomberg, E., Wold, S., and Odnevall Wallinder, I. (2016). Effect of sonication on particle dispersion, administered dose and metal release of non-functionalized, non-inert metal nanoparticles. J. Nanoparticle Res., 18.","DOI":"10.1007\/s11051-016-3597-5"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Ennas, G., Gedanken, A., Mannias, G., Kumar, V.B., Scano, A., Porat, Z., and Pilloni, M. (2022). Formation of Iron (III) Trimesate Xerogel by Ultrasonic Irradiation. Eur. J. Inorg. Chem., 2022.","DOI":"10.1002\/ejic.202101082"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Maeda, Y., Hayashi, Y., Fukushima, J., and Takizawa, H. (2021). Sonochemical effect and pore structure tuning of silica xerogel by ultrasonic irradiation of semi-solid hydrogel. Ultrason. Sonochem., 73.","DOI":"10.1016\/j.ultsonch.2021.105476"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1016\/j.procir.2016.11.173","article-title":"Indicators for Environmental Sustainability","volume":"61","author":"Dong","year":"2017","journal-title":"Procedia CIRP"},{"key":"ref_39","first-page":"1651","article-title":"Preparation of controlled porosity resorcinol formaldehyde xerogels for adsorption applications","volume":"32","author":"Oyedoh","year":"2013","journal-title":"Chem. Eng. Trans."},{"key":"ref_40","unstructured":"Ghrib, T.H. (2017). Carbon Xerogels: The Bespoke Nanoporous Carbons, IntechOpen. Chapter 3."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/j.apsusc.2017.11.053","article-title":"Magnetite (Fe3O4) nanoparticles: Synthesis, characterization and electrochemical properties","volume":"446","author":"Tipsawat","year":"2018","journal-title":"Appl. Surf. Sci."},{"key":"ref_42","first-page":"16","article-title":"Synthesis and Characterization of Magnetites Obtained from Mechanically and Sonochemically Assissted Co-precipitation and Reverse Co-precipitation Methods","volume":"5","author":"Sulistyaningsih","year":"2017","journal-title":"Int. J. Mater. Mech. Manuf."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Gaikwad, M.M., Sarode, K.K., Pathak, A.D., and Sharma, C.S. (2021). Ultrahigh rate and high-performance lithium-sulfur batteries with resorcinol-formaldehyde xerogel derived highly porous carbon matrix as sulfur cathode host. Chem. Eng. J., 425.","DOI":"10.1016\/j.cej.2021.131521"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"324","DOI":"10.1016\/j.carbon.2013.01.019","article-title":"Metal-doped carbon xerogels for the electro-catalytic conversion of CO2to hydrocarbons","volume":"56","author":"Ros","year":"2013","journal-title":"Carbon N. Y."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Prostredn\u00fd, M., Abduljalil, M., Mulheran, P., and Fletcher, A. (2018). Process Variable Optimization in the Manufacture of Resorcinol\u2013Formaldehyde Gel Materials. Gels, 4.","DOI":"10.3390\/gels4020036"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Martin, E., Prostredny, M., Fletcher, A., and Mulheran, P. (2020). Modelling organic gel growth in three dimensions: Textural and fractal properties of resorcinol\u2013formaldehyde gels. Gels, 6.","DOI":"10.3390\/gels6030023"},{"key":"ref_47","first-page":"37","article-title":"Synthesis of iron-doped resorcinol formaldehyde-based aerogels for the removal of Cr(VI) from water","volume":"4","author":"Verma","year":"2015","journal-title":"Green Process. Synth."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"466","DOI":"10.1016\/j.ultsonch.2015.06.016","article-title":"Direct and indirect sonication affect differently the microstructure and the morphology of ZnO nanoparticles: Optical behavior and its antibacterial activity","volume":"27","author":"Sharifalhoseini","year":"2015","journal-title":"Ultrason. Sonochem."},{"key":"ref_49","unstructured":"Calvo, E.G., Men\u00e9ndez, J.\u00c1., and Arenillas, A. (2011). Nanomaterials, IntechOpen."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1016\/j.jnoncrysol.2005.11.024","article-title":"Synthesis optimization of organic xerogels produced from convective air-drying of resorcinol-formaldehyde gels","volume":"352","author":"Job","year":"2006","journal-title":"J. Non. Cryst. Solids"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"2705","DOI":"10.1007\/s10853-009-3355-5","article-title":"The control of porosity at nano scale in resorcinol formaldehyde carbon aerogels","volume":"44","author":"Mirzaeian","year":"2009","journal-title":"J. Mater. Sci."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Martin, E., Prostredny, M., and Fletcher, A. (2021). Investigating the role of the catalyst within resorcinol\u2013 formaldehyde gel synthesis. Gels, 7.","DOI":"10.3390\/gels7030142"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1002\/adma.200390020","article-title":"Preparation and properties of resorcinol-formaldehyde organic and carbon gels","volume":"15","author":"Ritter","year":"2003","journal-title":"Adv. Mater."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1016\/j.jnoncrysol.2016.09.009","article-title":"Influence of alkaline compounds on the porosity of resorcinol-formaldehyde xerogels","volume":"452","author":"Calvo","year":"2016","journal-title":"J. Non. Cryst. Solids"},{"key":"ref_55","first-page":"544","article-title":"Heavy metal ions removal from aqueous solutions using carbon aerogels and xerogels","volume":"68","author":"Luzny","year":"2014","journal-title":"Chemik"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1016\/j.reactfunctpolym.2017.09.010","article-title":"Synthesis of hydrophobic resorcinol\u2013formaldehyde xerogels by grafting with silanes","volume":"120","author":"Arenillas","year":"2017","journal-title":"React. Funct. Polym."},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Dewes, R.M., Mendoza, H.R., Pereira, M.V.L., Lutz, C., and Gerven, T. (2022). Van Experimental and numerical investigation of the effect of ultrasound on the growth kinetics of zeolite A. Ultrason. Sonochem., 82.","DOI":"10.1016\/j.ultsonch.2022.105909"},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Ferri, S., Wu, Q., De Grazia, A., Polydorou, A., May, J.P., Stride, E., Evans, N.D., and Carugo, D. (2021). Tailoring the size of ultrasound responsive lipid-shelled nanodroplets by varying production parameters and environmental conditions. Ultrason. Sonochem., 73.","DOI":"10.1016\/j.ultsonch.2021.105482"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"619","DOI":"10.1016\/j.carbon.2003.12.072","article-title":"Porous carbon xerogels with texture tailored by pH control during sol-gel process","volume":"42","author":"Job","year":"2004","journal-title":"Carbon N. Y."},{"key":"ref_60","doi-asserted-by":"crossref","unstructured":"Kim, H.J., Choi, H., Sharma, A.K., Hong, W.G., Shin, K., Song, H., Kim, H.Y., and Hong, Y.J. (2021). Recyclable Aqueous Metal Adsorbent: Synthesis and Cu(II) Sorption Characteristics of Ternary Nanocomposites of Fe3O4 Nanoparticles@Graphene\u2013poly-N-Phenylglycine Nanofibers. J. Hazard. Mater., 401.","DOI":"10.1016\/j.jhazmat.2020.123283"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"192","DOI":"10.2166\/wst.2017.204","article-title":"Fe-FeS2 adsorbent prepared with iron powder and pyrite by facile ball milling and its application for arsenic removal","volume":"76","author":"Min","year":"2017","journal-title":"Water Sci. Technol."},{"key":"ref_62","doi-asserted-by":"crossref","unstructured":"Attia, S.M., Abdelfatah, M.S., and Mossad, M.M. (2017). Conduction mechanism and dielectric properties of pure and composite resorcinol formaldehyde aerogels doped with silver. J. Phys. Conf. Ser., 869.","DOI":"10.1088\/1742-6596\/869\/1\/012035"},{"key":"ref_63","doi-asserted-by":"crossref","unstructured":"Canal-Rodr\u00edguez, M., Rey-Raap, N., Men\u00e9ndez, J.\u00c1., Montes-Mor\u00e1n, M.A., Figueiredo, J.L., Pereira, M.F.R., and Arenillas, A. (2020). Effect of porous structure on doping and the catalytic performance of carbon xerogels towards the oxygen reduction reaction. Microporous Mesoporous Mater., 293.","DOI":"10.1016\/j.micromeso.2019.109811"},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1179\/143307512X13463991318033","article-title":"Synthesis, characterisation and magnetic examination of Fe, Co and Ni doped carbon xerogels","volume":"16","author":"Liu","year":"2012","journal-title":"Mater. Res. Innov."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"Alegre, C., Sebasti\u00e1n, D., G\u00e1lvez, M.E., Baquedano, E., Moliner, R., Aric\u00f2, A.S., Baglio, V., and L\u00e1zaro, M.J. (2017). N-Doped Carbon Xerogels as Pt Support for the Electro-Reduction of Oxygen. Materials, 10.","DOI":"10.3390\/ma10091092"},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"456","DOI":"10.1016\/j.carbon.2017.10.025","article-title":"Determinant influence of the electrical conductivity versus surface area on the performance of graphene oxide-doped carbon xerogel supercapacitors","volume":"126","author":"Arenillas","year":"2018","journal-title":"Carbon N. Y."},{"key":"ref_67","doi-asserted-by":"crossref","unstructured":"Sarwar, A., Wang, J., Khan, M.S., Farooq, U., Riaz, N., Nazir, A., Mahmood, Q., Hashem, A., Al-Arjani, A.B.F., and Alqarawi, A.A. (2021). Iron oxide (Fe3O4)-supported sio2 magnetic nanocomposites for efficient adsorption of fluoride from drinking water: Synthesis, characterization, and adsorption isotherm analysis. Water, 13.","DOI":"10.3390\/w13111514"},{"key":"ref_68","doi-asserted-by":"crossref","unstructured":"Niki\u0107, J., Tubi\u0107, A., Watson, M., Maleti\u0107, S., \u0160oli\u0107, M., Majki\u0107, T., and Agbaba, J. (2019). Arsenic removal from water by green synthesized magnetic nanoparticles. Water, 11.","DOI":"10.3390\/w11122520"},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"3221","DOI":"10.1007\/BF01139044","article-title":"Organic aerogels from the polycondensation of resorcinol with formaldehyde","volume":"24","author":"Pekala","year":"1989","journal-title":"J. Mater. Sci."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"3723","DOI":"10.1016\/j.carbon.2011.05.001","article-title":"Stability of a carbon gel electrode when used for the electro-assisted removal of ions from brackish water","volume":"49","author":"Haro","year":"2011","journal-title":"Carbon N. Y."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1016\/j.apcatb.2016.06.021","article-title":"Magnetic carbon xerogels for the catalytic wet peroxide oxidation of sulfamethoxazole in environmentally relevant water matrices","volume":"199","author":"Ribeiro","year":"2016","journal-title":"Appl. Catal. B Environ."},{"key":"ref_72","unstructured":"Amaringo, F.A., and Anaguano, A. (2013). Determination of the point of zero charge and isoelectric point of two agricultural wastes and their application in the removal of colorants. Rev. Investig. Agrar. y Ambient., 4."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1016\/j.cherd.2016.02.006","article-title":"A review of the kinetics adsorption models and their application to the adsorption of lead by an activated carbon","volume":"109","author":"Largitte","year":"2016","journal-title":"Chem. Eng. Res. Des."},{"key":"ref_74","doi-asserted-by":"crossref","unstructured":"L\u00f3pez-Luna, J., Ram\u00edrez-Montes, L.E., Martinez-Vargas, S., Mart\u00ednez, A.I., Mijangos-Ricardez, O.F., Gonz\u00e1lez-Ch\u00e1vez, M.d.C.A., Carrillo-Gonz\u00e1lez, R., Sol\u00eds-Dom\u00ednguez, F.A., Cuevas-D\u00edaz, M.d.C., and V\u00e1zquez-Hip\u00f3lito, V. (2019). Linear and nonlinear kinetic and isotherm adsorption models for arsenic removal by manganese ferrite nanoparticles. SN Appl. Sci., 1.","DOI":"10.1007\/s42452-019-0977-3"},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1080\/17518253.2014.955062","article-title":"Remediation of lead by pretreated red algae: Adsorption isotherm, kinetic, column modeling and simulation studies","volume":"7","author":"Hanbali","year":"2014","journal-title":"Green Chem. Lett. Rev."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.wri.2016.06.001","article-title":"Kinetics, isotherms and thermodynamic modeling of liquid phase adsorption of Rhodamine B dye onto Raphia hookerie fruit epicarp","volume":"15","author":"Inyinbor","year":"2016","journal-title":"Water Resour. Ind."},{"key":"ref_77","first-page":"133","article-title":"Determinaci\u00f3n de As (III) y As (V) en aguas naturales por generaci\u00f3n de hidruro con detecci\u00f3n por espectrometr\u00eda de absorci\u00f3n at\u00f3mica","volume":"34","author":"Quevedo","year":"2003","journal-title":"Rev. CENIC. Ciencias Qu\u00edmicas"}],"container-title":["Gels"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2310-2861\/9\/8\/618\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:22:39Z","timestamp":1760127759000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2310-2861\/9\/8\/618"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,7,30]]},"references-count":77,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2023,8]]}},"alternative-id":["gels9080618"],"URL":"https:\/\/doi.org\/10.3390\/gels9080618","relation":{},"ISSN":["2310-2861"],"issn-type":[{"value":"2310-2861","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,7,30]]}}}