Advertisement

Fresenius' Journal of Analytical Chemistry

, Volume 370, Issue 4, pp 413–418 | Cite as

Heterogeneity and lability of Pb(II) complexation by humic substances: practical interpretation tools

  • M. Filella
  • Raewyn M. Town
Original paper

Abstract

The complexation of Pb(II) by natural organic matter (NOM) is better described by taking into account the dependence of the strength of binding on metal loading conditions. The utility of a linear differential equilibrium function for interpretation of metal ion binding data is demonstrated. This approach considers the binding intensity (log K*) as a function of metal ion loading (ı = bound metal/binding site concentration). Three methods for calculating this function are presented:

– direct calculation from metal titration curves,

– direct calculation from polarograms, and

– compilation of data derived from interpretation of complexation in terms of one- or two- binding sites (e.g. Scatchard analysis), i.e. Cc (complexation capacity = effective site concentration)–K pairs.

Heterogeneity also impacts on the apparent lability of complexes; complexes formed at the lowest metal loadings are the least labile.

Keywords

Humic Substance Titration Curve Natural Organic Matter Metal Loading Binding Data 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • M. Filella
    • 1
  • Raewyn M. Town
    • 2
  1. 1.Department of Inorganic, Analytical and Applied Chemistry, University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland e-mail: montserrat.filella@cabe.unige.chCH
  2. 2.School of Chemistry, The Queen’s University of Belfast, Belfast BT9 5AG, Northern IrelandIE

Personalised recommendations