scoroditehfo.ppi

SPECIATION
  jobTitle                             "Fe-As-O2-H2O"      # aqueous, minerals and surface species
  calculationType                      ht1
  calculationMethod                    1
  mainSpecies                          As
  xmin                                 2.0
  xmax                                 12.0
  ymin                                 -85.0
  ymax                                 0.0
  resolution                           200

PLOT
  plotTitle                            "Fe-As-O<sub>2</sub>-H<sub>2</sub>O<br>(represented by a single adsorbed species)"
  xtitle                               pH
  pymin                                -20
  yscale                               pe
  extraText                            "extratextscorodite.dat"

CHEMISTRY

# first simulation

include 'ht1combined.inc'                                  # treat all Hfo-As surface species as one 'super' species for plotting

SOLUTION 1
   pH        1.8
   units     mol/kgw
   Fe(3)     1e-1
   Na        1e-1
   Cl        1e-1
   As        1e-2                                          # total As
END


# second simulation

include 'hfo.inc'                                          # add Hfo surface

USE solution 1
EQUILIBRIUM_PHASES 1
   Fix_H+ -<x_axis> NaOH 10
     -force_equality true
   O2(g)  <y_axis> 0.1
   Fe(OH)3(a) 0 0                                          # only consider this oxide

   Arsenolite 0 0                                          # possible As minerals
   Claudetite 0 0
   Scorodite  0 0
   As2O5(cr)  0 0
END