Remediation of polycyclic aromatic hydrocarbons polluted soil by biochar loaded humic acid activating persulfate: performance, process and mechanisms

Bioresour Technol. 2024 May:399:130633. doi: 10.1016/j.biortech.2024.130633. Epub 2024 Mar 27.

Abstract

The remediation for polycyclic aromatic hydrocarbons contaminated soil with cost-effective method has received significant public concern, a composite material, therefore, been fabricated by loading humic acid into biochar in this study to activate persulfate for naphthalene, pyrene and benzo(a)pyrene remediation. Experimental results proved the hypothesis that biochar loaded humic acid combined both advantages of individual materials in polycyclic aromatic hydrocarbons adsorption and persulfate activation, achieved synergistic performance in naphthalene, pyrene and benzo(a)pyrene removal from aqueous solution with efficiency reached at 98.2%, 99.3% and 90.1%, respectively. In addition, degradation played a crucial role in polycyclic aromatic hydrocarbons remediation, converting polycyclic aromatic hydrocarbons into less toxic intermediates through radicals of ·SO4-, ·OH, ·O2-, and 1O2 generated from persulfate activation process. Despite pH fluctuation and interfering ions inhibited remediation efficiency in some extent, the excellent performances of composite material in two field soil samples (76.7% and 91.9%) highlighted its potential in large-scale remediation.

Keywords: Degradation pathway; Persulfate activation; Polycyclic aromatic hydrocarbons; Soil remediation; Synergistic effect.

MeSH terms

  • Benzo(a)pyrene
  • Charcoal*
  • Humic Substances
  • Naphthalenes
  • Polycyclic Aromatic Hydrocarbons*
  • Pyrenes
  • Soil
  • Soil Pollutants* / analysis
  • Soil Pollutants* / metabolism

Substances

  • Humic Substances
  • Soil
  • Polycyclic Aromatic Hydrocarbons
  • biochar
  • Benzo(a)pyrene
  • Soil Pollutants
  • pyrene
  • Pyrenes
  • naphthalene
  • Naphthalenes
  • Charcoal