08 - Surface Complexation

This example corresponds to the “Example 8-Surface Complexation” from the Phreeqc manual. It can be retrieved from the Phreeqc Website.

Studies

This project contains 2 Studies.

• PhreeqcStudy: “study_08 - Surface Complexation”

Db used: “Phreeqc_dat” database

TITLE Example 8.--Sorption of zinc on hydrous iron oxides.

SURFACE_SPECIES

     Hfo_sOH  + H+ = Hfo_sOH2+

     log_k  7.18

     Hfo_sOH = Hfo_sO- + H+

     log_k  -8.82

     Hfo_sOH + Zn+2 = Hfo_sOZn+ + H+

     log_k  0.66

     Hfo_wOH  + H+ = Hfo_wOH2+

     log_k  7.18

     Hfo_wOH = Hfo_wO- + H+

     log_k  -8.82

     Hfo_wOH + Zn+2 = Hfo_wOZn+ + H+

     log_k  -2.32

SOLUTION 1

     -units  mmol/kgw

     pH      8.0

     Zn      @{$Zn_param$}@ 

     Na      100.    charge 

     N(5)    100.

SURFACE 1

     Hfo_sOH        5e-6    600.    0.09

     Hfo_wOH        2e-4

#     -donnan

PHASES

     Fix_H+

     H+ = H+

     log_k  0.0

#

EQUILIBRIUM_PHASES

     Fix_H+ @{$-1*pH_param$}@ NaOH 10.0

/n

• ParametricStudy: “parametricStudy”

Plots

This project contains 2 Plots.

• Plot 1: “Total Zn = 1e-7”

• Plot 2: “Total Zn = 1e-4”