WARNING: Fix_H+, Pure phase with add formula has not converged.

[Nlesani75]

Hi guys
i run my code and this error showed :"WARNING: Fix_H+, Pure phase with add formula has not converged." and also these errors but my chart were drowned.thanks for helping me. here its my code:
DATABASE C:\Program Files (x86)\USGS\Phreeqc Interactive 3.6.2-15100\database\phreeqc.dat
TITLE project1
SURFACE_MASTER_SPECIES
    Limsurf_a     Limsurf_aOH 
    Limsurf_c     Limsurf_cH   
SURFACE_SPECIES
Limsurf_aOH = Limsurf_aOH
    log_k     0
Limsurf_aOH = Limsurf_aO- + H+
    log_k     -12
Limsurf_aOH + CO3-2 + H+ = Limsurf_aHCO3 + OH-
    log_k     8.15
Limsurf_aOH + CO3-2 = Limsurf_aCO3- + OH-
    log_k     1.55
Limsurf_aOH + SO4-2 = Limsurf_aSO4- + OH-
    log_k     -0.1
Limsurf_cH = Limsurf_cH
    log_k     0
Limsurf_cH = Limsurf_c- + H+
    log_k     -5.1
Limsurf_cH + Ca+2 = Limsurf_cCa+ + H+
    log_k     -1.7
Limsurf_cH + Mg+2 = Limsurf_cMg+ + H+
    log_k     -2



SURFACE 1
    -equilibrate with solution 1
    Limsurf_a    2.5       0.11      0.2
    Limsurf_c    2.5
    -donnan 1e-9
    only_counter_ions false
    KNOBS; -iter 2000

SOLUTION 1 SW
    temp      25
    pH        7.6
    redox     pe
    units     ppm
    density   1
    Alkalinity 48 as HCO3-
    C(4)      0 as CO3-
    Ca        493 as Ca+
    Cl        23285
    K         434
    Mg        1637
    Na        12694
    S(6)      3025 as SO4-2
    -water    1 # kg
   
EQUILIBRIUM_PHASES 1
    Calcite   0 1e-3
SAVE solution 1

PHASES
    Fix_H+
    H+ = H+
    -log_k  0

SELECTED_OUTPUT
    -file                 sw3V1.sel
    -reset                 false

USER_PUNCH 
    -start
 10 FOR i = 6.5 to 8 STEP 0.5
 20 a$ = EOL$ + "USE solution 1" + CHR$(59) + " USE surface 1" + EOL$
 30  a$ = a$ + "EQUILIBRIUM_PHASES 2" + EOL$
 40 a$ = a$ + " Fix_H+ " + STR$(-i) + " HCl 0.1" + EOL$
 50 a$ = a$ + "END" + EOL$
 60 PUNCH a$
 70 NEXT i
 80 FOR i = 8 to 11 STEP 0.5
 90 a$ = EOL$ + "USE solution 1" + CHR$(59) + " USE surface 1" + EOL$
100 a$ = a$ + "EQUILIBRIUM_PHASES 2" + EOL$
110 a$ = a$ + " Fix_H+ " + STR$(-i) + " NaOH 0.1" + EOL$
120 a$ = a$ + "END" + EOL$
130 PUNCH a$
140 NEXT i
END
SELECTED_OUTPUT
    -file                 sw3V1-zp.sel
    -reset                true
    -molalities           Limsurf_cCa+  Limsurf_cMg+ Limsurf_c-  Limsurf_cH  Limsurf_aOH  Limsurf_aHCO3  Limsurf_aCO3-  Limsurf_aSO4-
USER_PUNCH 
    -start
10 PUNCH EDL("Psi","Limsurf")
    -end
USER_GRAPH 1 sw-sp
    -headings               pH Limsurf_cCa+ Limsurf_cMg+ Limsurf_c- Limsurf_cH Limsurf_aOH Limsurf_aHCO3 Limsurf_aCO3-  Limsurf_aSO4-
    -axis_titles            pH  "moles per kg water"
    -chart_title            "surface species"
    -axis_scale x_axis      5 12 1 1
    -axis_scale y_axis      1e-7 1e+1 1 1 log
  -start
10 GRAPH_X -LA("H+")
20 GRAPH_Y MOL("Limsurf_cCa+"), MOL("Limsurf_cMg+"), MOL("Limsurf_c-"), MOL("Limsurf_cH"), MOL("Limsurf_aOH"), MOL("Limsurf_aHCO3"), MOL("Limsurf_aCO3-"), , MOL("Limsurf_aSO4-")
  -end
   
USER_GRAPH 2 sw-zp
    -headings               pH zp
    -axis_titles            pH "zeta potential mV"
    -axis_scale x_axis      5 12 1 1
    -axis_scale y_axis      -40 10 5 5
    -initial_solutions      false
    -connect_simulations    true
    -plot_concentration_vs  x
  -start
10 GRAPH_X -LA("H+")
20 GRAPH_Y EDL("Psi","Limsurf")*1e3
  -end
     
INCLUDE$ sw3V1.sel
END
 i attach my run's log images

[dlparkhurst]

Couple things. First, I don't think there was enough base available to convert solution and surface to pH 11. Second, I think PHREEQC had a hard time at the transition between needing base or acid to adjust the pH.

Here is input that uses the trick described in Example 8 from the manual to add either acid or base as necessary. I also rearranged the calculation a bit to avoid writing the code for pH-adjustment simulations more than once.

Code: [Select]

TITLE project1
PHASES
Fix_H+
    H+ = H+
    log_k     0
NaCl
    NaCl = Cl- + Na+
    log_k     -20
END
TITLE project1
SURFACE_MASTER_SPECIES
    Limsurf_a     Limsurf_aOH
    Limsurf_c     Limsurf_cH   
SURFACE_SPECIES
Limsurf_aOH = Limsurf_aOH
    log_k     0
Limsurf_aOH = Limsurf_aO- + H+
    log_k     -12
Limsurf_aOH + CO3-2 + H+ = Limsurf_aHCO3 + OH-
    log_k     8.15
Limsurf_aOH + CO3-2 = Limsurf_aCO3- + OH-
    log_k     1.55
Limsurf_aOH + SO4-2 = Limsurf_aSO4- + OH-
    log_k     -0.1
Limsurf_cH = Limsurf_cH
    log_k     0
Limsurf_cH = Limsurf_c- + H+
    log_k     -5.1
Limsurf_cH + Ca+2 = Limsurf_cCa+ + H+
    log_k     -1.7
Limsurf_cH + Mg+2 = Limsurf_cMg+ + H+
    log_k     -2
END
SOLUTION 1 SW
    temp      25
    pH        7.6
    redox     pe
    units     ppm
    density   1
    Alkalinity 48 as HCO3-
    C(4)      0 as CO3-
    Ca        493 as Ca+
    Cl        23285
    K         434
    Mg        1637
    Na        12694
    S(6)      3025 as SO4-2
    -water    1 # kg
END
SURFACE 1
    -equilibrate with solution 1
    Limsurf_a    2.5       0.11      0.2
    Limsurf_c    2.5
    -donnan 1e-9
    only_counter_ions false
END
EQUILIBRIUM_PHASES 1
    Calcite   0 1e-3
END
USE solution 1
USE equilibrium_phases 1
USE surface 1
SAVE solution 1
SELECTED_OUTPUT
    -file                 sw3V1.sel
    -reset                 false
USER_PUNCH
    -start
 10 FOR i = 6.5 to 11 STEP 0.5
 20 a$ = EOL$ + "USE solution 1" + CHR$(59) + " USE surface 1" + EOL$
 30  a$ = a$ + "EQUILIBRIUM_PHASES 2" + EOL$
 40 a$ = a$ + " Fix_H+ " + STR$(-i) + " HCl 10" + EOL$
 45 a$ = a$ + " -force"  + EOL$
 47 a$ = a$ + " NaCl 0 10"  + EOL$
 50 a$ = a$ + "END" + EOL$
 60 PUNCH a$
 70 NEXT i
END
SELECTED_OUTPUT
    -file                 sw3V1-zp.sel
    -reset                true
    -molalities           Limsurf_cCa+  Limsurf_cMg+ Limsurf_c-  Limsurf_cH  Limsurf_aOH  Limsurf_aHCO3  Limsurf_aCO3-  Limsurf_aSO4-
USER_PUNCH
    -start
10 PUNCH EDL("Psi","Limsurf")
    -end
USER_GRAPH 1 sw-sp
    -headings               pH Limsurf_cCa+ Limsurf_cMg+ Limsurf_c- Limsurf_cH Limsurf_aOH Limsurf_aHCO3 Limsurf_aCO3-  Limsurf_aSO4-
    -axis_titles            pH  "moles per kg water"
    -chart_title            "surface species"
    -axis_scale x_axis      5 12 1 1
    -axis_scale y_axis      1e-7 1e+1 1 1 log
  -start
10 GRAPH_X -LA("H+")
20 GRAPH_Y MOL("Limsurf_cCa+"), MOL("Limsurf_cMg+"), MOL("Limsurf_c-"), MOL("Limsurf_cH"), MOL("Limsurf_aOH"), MOL("Limsurf_aHCO3"), MOL("Limsurf_aCO3-"), , MOL("Limsurf_aSO4-")
  -end
USER_GRAPH 2 sw-zp
    -headings               pH zp
    -axis_titles            pH "zeta potential mV"
    -axis_scale x_axis      5 12 1 1
    -axis_scale y_axis      -40 10 5 5
    -initial_solutions      false
    -connect_simulations    true
    -plot_concentration_vs  x
  -start
10 GRAPH_X -LA("H+")
20 GRAPH_Y EDL("Psi","Limsurf")*1e3
  -end
INCLUDE$ sw3V1.sel
END