Si-goethite3b.ppi

# from Hiemstra et al. (2007), J. Colloid Inteface Sci. 310, 8-17, Fig. 3(b)

SPECIATION
  calculationType                      custom
  calculationMethod                    1
  xmin                                 3.0
  xmax                                 11.0
  resolution                           81
  loopfile                             "loopSi.dat"

  numericTags                          <Goe_triOH> = 9.2 \
                                       <Goe_triONa> = -0.61 \
                                       <Goe_triOHNO3> = 8.50 \

                                       <Goe_uniOH2> = 9.2 \
                                       <Goe_uniOHNa> = -0.61 \
                                       <Goe_uniOH2NO3> = 8.50
PLOT
  plotTitle                            "Si remaining in solution after adsorption by goethite"
  xtitle                               pH
  ytitle                               "log dissolved Si (M)"
  pxmin                                3
  pxmax                                11
  pymajor                              1
  customxcolumn                        pH
  lines                                logSi
  extraText                            extratextSi.dat 
  linecolor                            red
  points                               dissSi
  pointColor                           red
  rimColor                             gray
  pointSize                            4
  labels                               1 2 3 4 5
  extradat                             fig3b.dat 
  changecolor                          t
  labelSize                            0

CHEMISTRY

SELECTED_OUTPUT
  -reset false

SOLUTION 1
  Temp      25
  pH        2.9
  units     mol/kgw

  Si        <SiT> mmol/kgw
  Na        1e-1                                           # background electrolyte
  N(5)      1e-1

include 'ecosatSi.dat'                                     # aqueous species database
include 'cdmusic_hiemstra.dat'                             # adsorbed species database

USER_PUNCH
-headings pH logSi
10 PUNCH -la("H+"), log10(TOT("Si"))

PHASES ; Fix_H+; H+ = H+ ; log_k 0

SURFACE 1
  Goe_uniOHH0.5 3.45 100 <mass>  # sites/nm2  m2/g  g
    -cap    0.92  0.92           # C1  C2  (in F/m2)
  Goe_triOH0.5  2.7
    -cd_music
    -sites_units density

EQUILIBRIUM_PHASES 1
  Fix_H+  -<x_axis> NaOH
    -force_equality true
  O2(g)  -0.7
END