Role of sorbent surface functionalities and microporosity in 2,2′,4,4′-tetrabromodiphenyl ether sorption onto biochars

https://doi.org/10.1016/S1001-0742(12)60222-8Get rights and content

Abstract

The study provides insight into the combined effect of sorbent surface functionalities and microporosity on 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) sorption onto biochars. A series of biochars prepared under different conditions were used to test their sorption behaviors with BDE-47. The extents of sorption behaviors were parameterized in terms of the single-point adsorption equilibrium constant (Koc) at three equilibrium concentration (Ce) levels (0.001Sw (solubility), 0.005Sw, and 0.05Sw) which was determined using the Freundlich model. To elucidate the concentration-dependent dominant mechanisms for BDE-47 sorption onto biochars, Koc was correlated with four major parameters using multiple parameter linear analysis accompanied with significance testing. The results indicated that at low concentration (Ce = 0.001Sw), the surface microporosity term, which represented a pore-filling mechanism, contributed significantly to this relationship, while as concentration was increased to higher levels, surface functionality related to surface adsorption began to take the dominant role, which was further confirmed by the results of Polanyi-based modeling. Given the above results, a dual mode model based on Dubinin-Radushkevich and de Boer-Zwikker equations was adopted to quantitatively assess the changes of significance of surface adsorption as well as that of pore filling with sorption process development. In addition, UV spectra of four typical aromatic compounds which represented the key structural fragments of biochars before and after interactions with BDE-47 were analyzed to determine the active functional groups and supply complementary evidence for the dominant interaction force for surface adsorption, based on which π–π electron-donor-acceptor interaction was proposed to contribute greatly to surface adsorption.

References (30)

  • XL Zhang et al.

    Spatial distribution and vertical profile of polybrominated diphenyl ethers, tetrabromobisphenol A, and decabro-modiphenylethane in river sediment from an industrialized region of South China

    Environmental Pollution

    (2009)
  • B Chefetz et al.

    Relative role of aliphatic and aromatic moieties as sorption domains for organic compounds: A review

    Environmental Science & Technology

    (2009)
  • BL Chen et al.

    Transitional adsorption and partition of nonpolar and polar aromatic contaminants by biochars of pine needles with different pyrolytic temperatures

    Environmental Science & Technology

    (2008)
  • G Cornelissen et al.

    Extensive sorption of organic compounds to black carbon, coal, and kerogen in sediments and soils: Mechanisms and consequences for distribution, bioaccumulation, and biodegradation

    Environmental Science & Technology

    (2005)
  • YP Duan et al.

    Polybrominated diphenyl ethers in background surface soils from the Yangtze River Delta (YRD), China: occurrence, sources, and inventory

    Environmental Science and Pollution Research

    (2010)
  • Cited by (20)

    • Understanding the role of biochar in affecting BDE-47 biodegradation by Pseudomonas plecoglossicida: An integrated analysis using chemical, biological, and metabolomic approaches

      2022, Water Research
      Citation Excerpt :

      As shown in Table S4, the order of log kd was different at three Ce levels (Ce= 0.01Sw, Ce= 0.1Sw, Ce= 1Sw) for six biochars. This result indicated that the predominant adsorption mechanisms might be changed with the concentration variation (Xin et al., 2013). Chen et al. (2008) demonstrated pore-filling was the predominant mechanism for HOCs adsorption at low concentration levels, while the dominant role of the pore-filling mechanism was replaced by surface adsorption as the concentration gradually increased.

    • Remediation of organic pollutants by Brassica species

      2020, Handbook of Bioremediation: Physiological, Molecular and Biotechnological Interventions
    View all citing articles on Scopus
    View full text