Effect of ferrous iron on arsenate sorption to amorphous ferric hydroxide

Muhammed Mukiibi, Wendell P Ela, Avelino E Saez

Research output: Chapter in Book/Report/Conference proceedingConference contribution

6 Citations (Scopus)

Abstract

Amorphous ferric hydroxide (AFH) sorbents are commonly used for removal of arsenate from water. When disposed in microbially active, reducing environments, such as landfills, Fe(II) will be generated by reductive dissolution of the AFH surface and arsenate will be desorbed. However, the observed ratio of arsenate (and, in fact, total arsenic) to total iron in the leachate is not consistent with the original ratio of arsenate to iron on the AFH. Work to determine if ferrous iron re-adsorption to the AFH can partially explain this inconsistency is described. As pH increases above 7, Fe(II) increasingly sorbs onto the AFH surface. This sorption is largely independent of ionic strength and somewhat irreversible at high pH. In contrast, arsenate partitioning to AFH decreases with increasing pH. However, over the pH range from 5 to 9, the presence of Fe(II) sorbed to the AFH surface increases the capacity for arsenate sorption. In addition, when no Fe(II) is present, arsenate binding is largely to surface sites inaccessible to Fe(II) binding. The results are also consistent with Fe(II) sorption to AFH sites, otherwise unfavorable to arsenate binding and transformation of those sites into arsenate-amenable binding sites.

Original languageEnglish (US)
Title of host publicationAnnals of the New York Academy of Sciences
Pages335-345
Number of pages11
Volume1140
DOIs
StatePublished - Oct 2008

Publication series

NameAnnals of the New York Academy of Sciences
Volume1140
ISSN (Print)00778923
ISSN (Electronic)17496632

Fingerprint

Sorption
Iron
Waste Disposal Facilities
arsenic acid
ferric hydroxide
Arsenic
Sorbents
Land fill
Ionic strength
Osmolar Concentration
Adsorption
Dissolution
Binding Sites
Water

Keywords

  • ABSR
  • Amorphous ferric hydroxide
  • Arsenate
  • Arsenic residuals disposal
  • As(V)
  • Fe(II)
  • Ferrous iron
  • Sorption
  • Water treatment residuals

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

Mukiibi, M., Ela, W. P., & Saez, A. E. (2008). Effect of ferrous iron on arsenate sorption to amorphous ferric hydroxide. In Annals of the New York Academy of Sciences (Vol. 1140, pp. 335-345). (Annals of the New York Academy of Sciences; Vol. 1140). https://doi.org/10.1196/annals.1454.024

Effect of ferrous iron on arsenate sorption to amorphous ferric hydroxide. / Mukiibi, Muhammed; Ela, Wendell P; Saez, Avelino E.

Annals of the New York Academy of Sciences. Vol. 1140 2008. p. 335-345 (Annals of the New York Academy of Sciences; Vol. 1140).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Mukiibi, M, Ela, WP & Saez, AE 2008, Effect of ferrous iron on arsenate sorption to amorphous ferric hydroxide. in Annals of the New York Academy of Sciences. vol. 1140, Annals of the New York Academy of Sciences, vol. 1140, pp. 335-345. https://doi.org/10.1196/annals.1454.024
Mukiibi M, Ela WP, Saez AE. Effect of ferrous iron on arsenate sorption to amorphous ferric hydroxide. In Annals of the New York Academy of Sciences. Vol. 1140. 2008. p. 335-345. (Annals of the New York Academy of Sciences). https://doi.org/10.1196/annals.1454.024
Mukiibi, Muhammed ; Ela, Wendell P ; Saez, Avelino E. / Effect of ferrous iron on arsenate sorption to amorphous ferric hydroxide. Annals of the New York Academy of Sciences. Vol. 1140 2008. pp. 335-345 (Annals of the New York Academy of Sciences).
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