Can't calculate the surface complexation

[Yongqiang]

Hi. I did the following calcualtion on surface complexation. But it can't calculate. I checked the syntax. But didn't find any erro. Does anybody encounter the same problem. Thank you.





DATABASE c:\phreeqc\database\LLNL.DAT
TITLE Sorption parameter calibration
SURFACE_MASTER_SPECIES
     Ca_s   Ca_sCaOH-0.75
     Ca_w   Ca_wCO3H+0.75
SURFACE_SPECIES
   Ca_sCaOH-0.75 = Ca_sCaOH-0.75
   log_k = 0
   Ca_wCO3H+0.75 = Ca_wCO3H+0.75
   log_k = 0
   Ca_sCaOH-0.75 + H+ = Ca_sCaOH2+0.25
   log_k  1
   Ca_wCO3H+0.75 + OH- = Ca_wCO3-0.25 + H2O
   log_k 1
   Ca_sCaOH-0.75 + Ca+2 = Ca_sCaOHCa+1.25
   log_k 1
   Ca_sCaOH-0.75 + Mg+2 = Ca_sCaOHMg+1.25
   log_k 1
        Ca_wCO3H+0.75 + CO3-2 = Ca_wCO3HCO3-1.25
         log_k 1
        Ca_wCO3H+0.75 + SO4-2 = Ca_wCO3HSO4-1.25
        log_k 1
        Ca_wCO3H+0.75 + HCO3- = Ca_wCO3HHCO3-0.25
        log_k    1
   Ca_sCaOH-0.75 + Na+ = Ca_sCaOHNa+0.25
   log_k 1
   Ca_wCO3H+0.75 + Cl- = Ca_wCO3HCl-0.25
        log_k 1
SURFACE 1
        -sites_units   density
   -cd_music
   Ca_sCaOH-0.75      2.475    0.11.  10
   Ca_wCO3H+0.75      2.475
   -capacitance  0.98 0.73
   -Donnan      
   -only_counter_ions  true
END

SOLUTION 1 0 PPM
      -units  mol/L
END     
SOLUTION 2 1000 PPM
   -units  mol/L
     Na        0.011833333
     Ca      0.0015
     Mg      0.0015
     Cl      0.01780
END   
SOLUTION 3 5000PPM
     -units  mol/L
     Na        0.059166667
     Ca      0.0075
     Mg      0.0075
     Cl      0.089
END
SOLUTION 4 15000PPM
     -units  mol/L
     Na        0.1775
     Ca      0.0225
     Mg      0.0225
     Cl      0.267
END
SOLUTION 5 25000PPM
     -units  mol/L
     Na        0.295833333
     Ca      0.0375
     Mg      0.0375
     Cl      0.445
END
PHASES
   NaNO3
   NaNO3 = Na+ + NO3-
   log_K -20
   Fix_H+
   H+ = H+
   log_K 0
END
SELECTED_OUTPUT
   -file Base.prn
   -reset false
   -high_precision true
USER_PUNCH
   -start
   10 Adsorption = EDL("psi1","Ca")*1000
   20 PUNCH Adsorption
   -end

USE SOLUTION 1; USE SURFACE 1;  EQUILIBRIUM_PHASES 1; CO2(g) -3.5;  END
USE SOLUTION 2; USE SURFACE 1;   EQUILIBRIUM_PHASES 1; CO2(g) -3.5;  END
USE SOLUTION 3; USE SURFACE 1;   EQUILIBRIUM_PHASES 1; CO2(g) -3.5;  END
USE SOLUTION 4; USE SURFACE 1;   EQUILIBRIUM_PHASES 1; CO2(g) -3.5;  END
USE SOLUTION 5; USE SURFACE 1;   EQUILIBRIUM_PHASES 1; CO2(g) -3.5;  END

[dlparkhurst]

I suggest you not use -only_counter_ions

[dlparkhurst]

Also, you must define surface species to be cd_music species with specified charge distribution in SOLUTION_SPECIES.

[Yongqiang]

Also, you must define surface species to be cd_music species with specified charge distribution in SOLUTION_SPECIES.

Hi David,

Could you provide an example on how to define the specified charge distribution in SOLUTION_SPECIES? I went through the manual but didn't find an example?

Best Regards,
Yongqiang

[dlparkhurst]

Example data block 2 in SOLUTION_SPECIES shows an example, but you will need to read the work of Hiemstra to use it correctly.

[Yongqiang]

Example data block 2 in SOLUTION_SPECIES shows an example, but you will need to read the work of Hiemstra to use it correctly.

Hi David,

Thanks for your help. I understand how to define cd-music model. I think you may refer to Example data block 2 in SURFACE_SPECIES.

Best Regards,
Yongqiang