{
  "abstract": "This study evaluated biochars derived from Cnidoscolus aconitifolius (chaya) leaf residues for methylene blue (MB) removal from water. Two materials were produced under identical thermal conditions from untreated biomass (CCP-A) and post-extraction biomass (CCP-B), allowing direct assessment of the effect of metabolite extraction. Characterization by SEM/EDS, XRD, FTIR, Raman spectroscopy, XPS, and N2 adsorption-desorption showed that extraction altered surface chemistry and textural properties, increasing oxygen-containing functionalities and BET surface area from 1.92 to 6.10 m2 g-1 and decreasing mean pore diameter from 14.1 to 8.4 nm. These differences were associated with improved MB removal by CCP-B under dark and irradiation conditions. Kinetic analysis was consistent with multiple transport contributions. Among the equilibrium models, Langmuir yielded the highest linearized R2 and a model-estimated qmax of 155.3 mg g-1, whereas degrees-of-freedom-adjusted RMSE analysis on the original qe scale did not identify a single unequivocally superior model. Despite its relatively low BET surface area, the MB uptake of CCP-B suggests that adsorption cannot be explained solely by the dry surface accessible to N2 at 77 K. Oxygen-containing functionalities may contribute to electrostatic attraction and hydrogen bonding, whereas aromatic domains may support π-π interactions. Under UV and simulated solar irradiation, CCP-B reached overall removal efficiencies of 98.6% and 93.8%, respectively. Because adsorption and possible light-induced transformations were not quantified independently, these values represent overall photo-assisted removal. Inhibition by isopropanol was consistent with possible participation of hydroxyl radicals or related reactive oxygen species; however, this evidence was indirect, the species were not detected directly, and degradation products and mineralization were not evaluated. CCP-B removal efficiency decreased from approximately 92% to 31% over five adsorption-drying reuse cycles, indicating limited reuse performance without effective regeneration. Under the conditions evaluated, metabolite extraction before carbonization modified the surface properties of chaya-derived biochar and was associated with improved MB removal.",
  "abstract_shown": true,
  "affiliations": [
    "Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Mérida, Mérida, Yucatán, Mexico"
  ],
  "article_type": "Research Article",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Viviana Roche-Llerena"
    },
    {
      "name": "Leonardo Hernández"
    },
    {
      "name": "Raúl Pareja-Rodríguez"
    },
    {
      "name": "Geonel Rodríguez-Gattorno"
    },
    {
      "name": "María A. Fernández-Herrera"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/d3df0g5s4w352.bib",
  "cited_by": 0,
  "doi": "10.1371/journal.pone.0358748",
  "fulltext_url": null,
  "id": "d3df0g5s4w352",
  "issns": [
    "1932-6203"
  ],
  "landing_url": "https://doi.org/10.1371/journal.pone.0358748",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2312|Adsorption and biosorption for pollutant removal"
    ],
    [
      "plos",
      "/Biology and life sciences/Biochemistry/Metabolism/Metabolites"
    ],
    [
      "plos",
      "/Biology and life sciences/Plant science/Plant anatomy/Leaves"
    ],
    [
      "plos",
      "/Physical sciences/Chemistry/Chemical compounds/Hydrocarbons/Methylenes/Methylene blue"
    ],
    [
      "plos",
      "/Physical sciences/Chemistry/Chemical compounds/Reactive oxygen species"
    ],
    [
      "plos",
      "/Physical sciences/Chemistry/Chemical radicals/Hydroxyl radicals"
    ],
    [
      "plos",
      "/Physical sciences/Chemistry/Physical chemistry/Chemical bonding/Hydrogen bonding"
    ],
    [
      "plos",
      "/Physical sciences/Chemistry/Physical chemistry/Chemical radicals/Hydroxyl radicals"
    ],
    [
      "plos",
      "/Physical sciences/Chemistry/Physical chemistry/Sorption/Adsorption"
    ],
    [
      "plos",
      "/Research and analysis methods/Spectrum analysis techniques/Electron beam spectrum analysis techniques/X-ray photoelectron spectroscopy"
    ]
  ],
  "openalex": "W7214185069",
  "pdf_url": "https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0358748&type=printable",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-24",
  "publisher": "Public Library of Science",
  "ris": "https://research.draconitic.com/paper/d3df0g5s4w352.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:43Z",
      "native_id": "10.1371/journal.pone.0358748",
      "source": "plos",
      "url": "https://doi.org/10.1371/journal.pone.0358748"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "plos:physical chemistry",
      "subfield": "physical"
    }
  ],
  "title": "Methylene blue removal from water using chaya-derived biochar: Effect of metabolite extraction on adsorption",
  "title_text": "Methylene blue removal from water using chaya-derived biochar: Effect of metabolite extraction on adsorption",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:43Z",
  "url": "https://research.draconitic.com/paper/d3df0g5s4w352",
  "venue": "PLOS One",
  "versions": []
}