Fe solubility diagram

[shellaarinda10]

Hello, I am really a new user of PHREEQC software. And I want to make a Fe solubility diagram in sulfuric acid condition. The x axis want to be a log (SO4-2) and the y axis is log conc. I already tried, and it shows no error, but the graph won't appear. Can you help me to find what is wrong with my code? Thank you very much.

Code: [Select]

PHASES
H2SO4(l)
    H2SO4 = 2H+ + SO4-2
    log_k   -1.0209

SOLUTION 1
    temp 50.0
    pH 0.0 charge
    units mol/kgw
    Fe(3) 1.435
    S(6)  1

SOLUTION 2
    temp 50.0
    pH 0.0 charge
    units mol/kgw
    Fe(3) 1.435
    S(6)  2

SOLUTION 3
    temp 50.0
    pH 0.0 charge
    units mol/kgw
    Fe(3) 1.435
    S(6)  3

SOLUTION 4
    temp 50.0
    pH 0.0 charge
    units mol/kgw
    Fe(3) 1.435
    S(6)  4

SOLUTION 5
    temp 50.0
    pH 0.0 charge
    units mol/kgw
    Fe(3) 1.435
    S(6)  5


SELECTED_OUTPUT
    -file output_anlanatmos.txt
    -pH true
    -totals Fe S
    -saturation_indices
    -equilibrium_phases

USER_GRAPH 1
    -headings               SO4-2 Fe+3 FeSO4+ Fe(SO4)2- Fe2(OH)2+4 FeOH+2 Fe3(OH)4+5 Fe(OH)2+ Fe(OH)3 Fe(OH)4-
    -axis_titles            "log so4-2" "log conc" ""
    -chart_title            "Fe solubility"
    -initial_solutions      false
    -connect_simulations    true
    -plot_concentration_vs  x
  -start
10 graph_x log10(tot("S(6)"))
20 graph_y mol("Fe+3")
30 graph_y mol("FeSO4+")
40 graph_y mol("Fe(SO4)2-")
50 graph_y mol("Fe2(OH)2+4")
60 graph_y mol("FeOH+2")
70 graph_y mol("Fe3(OH)4+5")
80 graph_y mol("Fe(OH)2+")
90 graph_y mol("Fe(OH)3")
100 graph_y mol("Fe(OH)4-")
  -end
    -active                 true
END


[dlparkhurst]

You need the following in USER_GRAPH

Code: [Select]

    -initial_solutions      true


[shellaarinda10]

Thank you very much, Professor David! I truly appreciate your time and assistance with my question!