Kinetics and isotherm analysis of 2,4-dichlorophenoxyl acetic acid adsorption onto soil components under oxic and anoxic conditions

Isaac A Ololade, Folasade Alomaja, Nurudeen A Oladoja, Oluwaranti O Ololade, Femi F Oloye

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

2,4-dichlorophenoxyl acetic acid (2,4-D, pKa = 2.8) is used extensively as a herbicide in agricultural practices. Its sorption behavior on both untreated and soils treated to significantly remove specific components (organic and iron and manganese [Fe-Mn] oxides and hydroxides phases) was investigated under oxic and anoxic conditions. The chemical and structural heterogeneity of the soil components were characterized by elemental analysis and X-ray diffraction (XRD). The coexistence of the various components seems to either mask sorption sites on the untreated soil surfaces or inhibit interlayer diffusion of 2,4-D. All sorption data conform to the Freundlich description and a pseudo-second-order kinetic model. There was a strong positive correlation between sorption capacity K(d), and surface area (r(2) ≤ 0.704), but a negative correlation was uncovered with both pH and organic carbon (r(2) ≤ -0.860). The results indicate that 2,4-D is preferably sorbed under oxic rather than anoxic conditions and it is greater on soils containing a high Fe content. There was incomplete 2,4-D sorption reversibility, with desorption occurring more rapidly under anoxic conditions. The study suggests that stimulation of Fe III reduction could be used for the bioremediation of a 2,4-D-contaminated site.

Original languageEnglish
Pages (from-to)492-503
Number of pages12
JournalJournal of Environmental Science and Health, Part B
Volume50
Issue number7
DOIs
Publication statusPublished - 2015

Keywords

  • 2,4-Dichlorophenoxyacetic Acid
  • Adsorption
  • organic matter
  • Herbicide
  • Hydrogen-Ion Concentration
  • Kinetics
  • Manganese Compounds
  • Oxides
  • Soil
  • Soil components
  • X-Ray Diffraction
  • sorption
  • desorption

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Environmental Science(all)
  • Medicine(all)

Fingerprint Dive into the research topics of 'Kinetics and isotherm analysis of 2,4-dichlorophenoxyl acetic acid adsorption onto soil components under oxic and anoxic conditions'. Together they form a unique fingerprint.

  • Cite this