Comparison of the Effects of Hydroxamate Siderophores on Lead and Cadmium Adsorption to Kaolinite

Master's Thesis
Thumbnail

Abstract

Siderophores are Fe(III)-specific organic ligands biosynthesized by microbes in Fe-deficient environments. They also complex other metals, such as Pb and Cd, influencing metal mobility. This study compared the effects of siderophores desferrioxamine-B (DFO-B), desferrioxamine-D (DFO-D1), desferrioxamine-E (DFO-E), as well as siderophore-like ligand acetohydroxamic acid (aHA) on Pb and Cd (except for DFO-E) adsorption to kaolinite (KGa-1b) at pH 4.5 to 9, in 0.1 M NaClO4, at 22oC, in the dark. At pH > 6, all of the ligands inhibited Pb adsorption with inhibition increasing in the order aHA < DFO-D1 < DFO-B < DFO-E. At lower pH, the presence of DFO-B slightly enhanced Pb adsorption. These ligands also inhibited Cd adsorption at pH > 8, but had no effect at low pH. Modeling the systems with PHREEQC suggested that the siderophores in solution out-competed the kaolinite surface for the metal cations, thus causing decreased adsorption at high pH.

Attributes

Attribute NameValues
URN
  • etd-04132004-142711

Author Sarah Elizabeth Hepinstall
Advisor Patricia Maurice
Contributor Jeremy Fein, Committee Member
Contributor Patricia Maurice, Committee Chair
Contributor Peter Burns, Committee Member
Degree Level Master's Thesis
Degree Discipline Civil and Environmental Engineering and Earth Sciences
Degree Name MS
Defense Date
  • 2004-03-25

Submission Date 2004-04-13
Country
  • United States of America

Subject
  • kaolinite

  • cadmium

  • siderophores

  • adsorption

  • lead

Publisher
  • University of Notre Dame

Language
  • English

Record Visibility and Access Public
Content License
  • All rights reserved

Departments and Units

Files

Please Note: You may encounter a delay before a download begins. Large or infrequently accessed files can take several minutes to retrieve from our archival storage system.