Is the Surface Complexation Modules can fit the batch experiment date?

[weird]

Dear Sir,
I have following doubt related to surface complexation:
When I read the articles "Stream-Subsurface exchange of Zinc in the Prensence of Silica and Kaolinite Colloids"(Jianhong Ren and AARON I. PACKMAN.  Environ.Sci.Technol.2004,38,6571-6581).  The article said batch experiments were conducted to characterize zinc sorption/desorption interactions with all sediments over the PH range used in the flum experiments. Batch experiemnt results were simulated using PHREEQC based on the equilibrium constants estimated from titration date. But the FIGURE 3(look at the attachment) title is batch experiment date and fitting from phreeqc.
So, is the PHREEQC can fitting the batch experiment date or simulate the  reaction processon on the basis of experiment initial conditions then compare the results.

[dlparkhurst]

PHREEQC does not have built-in fitting capability. It can simulate sorption given C0, reactions, and equilibrium constants.

However, the simulation can be linked to a parameter estimation code, like PEST. A PHREEQC input file can be used as a template with parameters identified, and PEST can adjust parameters to provide a best fit to a set of experimental results.

PhreePlot is another code that can provide parameter estimation based on PHREEQC simulations.

[weird]

Thanks sir, your reply has been solved my confusion.

[Charlie]

Hi Weird,
Prof David Sherman (University of Bristol, http://mineral.gly.bris.ac.uk/) frequently works on surface complexation modelling, and has developed a fitting code EQLFOR for this purpose.  His publications would be of interest to you and he might now have an edition of his code that he is willing to share.  If you have questions regarding surface complexation, I might also be able to answer them.