Community Research and Development Information Service - CORDIS


There is a growing need to consider the influence of organic macromolecules on the speciation of ions in natural waters. A simple discrete ligand approach to the binding of protons/cations to organic macromolecules is inappropriate for representing heterogeneities of binding site distributions. A more realistic approach, incorporated into the speciation code PHREEQE, retains the discrete ligand approach but modifies the binding intensities using an electrostatic (surface complexation) model. To allow for different conformations of natural organic material, two alternative concepts were incorporated, assuming that the organic molecules form rigid, impenetrable spheres or flat surfaces. The theoretical concept is discussed and the relevant changes to the standard PHREEQE code are explained. Improved output facilities for data transfer to other computers are introduced. Examples where the model is tested against literature data are presented and practical problems are discussed.

Additional information

Authors: FALCK W E, British Geological Survey, Fluid Processes Research Group, Keyworth, Nottingham (GB)
Bibliographic Reference: EUR 13202 EN (1991) 32 pp., FS, ECU 5
Availability: (2)
ISBN: ISBN 92-826-0462-4
Record Number: 199110170 / Last updated on: 1994-12-02
Original language: en
Available languages: en