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Cited by 105Adsorption and biosorption for pollutant removalThermochemical Biomass Conversion ProcessesEnvironmental remediation with nanomaterials

Morphology of Modified Biochar and Its Potential for Phenol Removal from Aqueous Solutions

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Komnitsas, Kostas A., Zaharaki, Dimitra·2016·Frontiers in Environmental Science
DOI 10.3389/fenvs.2016.00026
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Abstract

In the present study, the efficiency of phenol removal from synthetic aqueous solutions by chemically modified biochar with the use of 1M KOH or 1M FeCl3 was investigated. Initially, biochar was produced after slow pyrolysis of three different agricultural wastes, namely pistachio (Pistacia vera L.) shells, pecan (Carya illinoinensis) shells and wood sawdust. The quality of biochar was assessed by evaluating its main properties, such as pH, surface area, porosity and C content. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were used for the identification of biochar’s structure. The efficiency of phenol removal from synthetic solutions was assessed with the use of kinetic and equilibrium experiments. The experimental results show that the KOH-modified biochar exhibited the highest phenol removal efficiency. Hydrophobic sorption on its surface is the main phenol removal mechanism. The pseudo-second order model fits best the kinetic data, while the Freundlich model, as deduced from an equilibrium study describes very well sorption of phenols on all biochars examined.

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  • Chemically activated biochars possess more oxygen-containing functional groups (e.g., carboxyl, hydroxyl, carbonyl) that facilitate phenol adsorption via hydrogen bonding and π-π interactions.

    “Chemically activated biochars possess more oxygen-containing functional groups (e.g., carboxyl, hydroxyl, carbonyl) that facilitate phenol adsorption via hydrogen bonding and π-π interactions [20,21].”

    From Innovative Valorization of Wood Panel Waste into Activated Biochar for Efficient Phenol Adsorption (2025) · cites this paper as [20]

    The Characterization of Biochars section identifies hydroxyl, carbonyl and carboxylic groups, and the Adsorption of Phenols on Biochars section reports greater phenol adsorption by KOH-modified biochars. Neither section establishes that modification increases those oxygen-containing groups or that hydrogen bonding and π–π interactions facilitate adsorption; the paper instead identifies hydrophobic sorption as the probable main mechanism. Page numbers are unavailable in our copy. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Biochar has a high porosity with a specific surface area of up to 1500 m2/g.

    “Its high porosity (with a specific surface area of up to 1500 m 2 /g), modular carbon structure, and ability to trap organic contaminants via π-π interactions and hydrogen bonds make it an excellent choice for water decontamination [19][20][21].”

    From Innovative Valorization of Wood Panel Waste into Activated Biochar for Efficient Phenol Adsorption (2025) · cites this paper as [20]

    The Introduction describes biochar as porous, and Characterization of Biochars reports increased porosity after modification. That section gives 572.4 m²/g as the highest surface area among the biochars studied; it does not support the stated figure of 1500 m²/g. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • The literature acknowledges the importance of oxygen-containing functional groups, as demonstrated by FTIR analyses in previous studies.

    “The literature acknowledges the importance of these functional groups, as demonstrated by FTIR analyses in previous studies [20,21,25].”

    From Innovative Valorization of Wood Panel Waste into Activated Biochar for Efficient Phenol Adsorption (2025) · cites this paper as [20]

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Cited by

Sorted by citations

Authors
Komnitsas, K. A., & Zaharaki, D.
Affiliations
Technical University of Crete (GR)
Corresponding author
Komnitsas, Kostas A.
ORCID
Komnitsas, Kostas A.
Venue
Frontiers in Environmental Science
Publisher
Frontiers Media SA
Published
2016-04-08
Volume
4
ISSN
2296-665X (ISSN-L)
DOI
10.3389/fenvs.2016.00026
OpenAlex
W2313995659
Cited by
105
References
4
Citations by year
2026: 9 · 2025: 16 · 2024: 10 · 2023: 16 · 2022: 10 · 2021: 18 · 2020: 8 · 2019: 8 · 2018: 2 · 2017: 7 · 2016: 1
FWCI
3.56
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
  • Frontiers in Environmental Science (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Topics
  • Physical Sciences › Environmental Science › Water Science and Technology › Adsorption and biosorption for pollutant removal
  • Physical Sciences › Engineering › Biomedical Engineering › Thermochemical Biomass Conversion Processes
  • Physical Sciences › Engineering › Biomedical Engineering › Environmental remediation with nanomaterials
Keywords
biochar, phenol removal, KOH modification, FeCl3 modification, slow pyrolysis, agricultural waste, pistachio shell, pecan shell, sawdust, adsorption, pseudo-second-order kinetics, Freundlich isotherm, wastewater treatment

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