The name is absent

Chapter 4

Both -AIO' and -SiO' sites can adsorb divalent cations. In the surface
adsorption of divalent cations, these two sites are not distinguishable. In Eq.
[4.13], -AIO' and -SiO' sites having the same equilibrium constant is assumed.
For positively charged sites, -AIOH₂⁺ and -SiOH₂⁺ sites having the same
equilibrium constant for adsorption of anions is also assumed.

Here the adsorption of HSiOs' ion is considered instead of SiO3²' ion,
because the concentration of HSiOs' ion is much higher than SiO₃²' ion in the
brine. For the similar reason, H₃SiO₄' ion and CeH₅O₇³' ion have the highest
concentration and are considered in the adsorption. Forweak electrolyte, such as
SiO₃²' ion, ion dissociation equilibrium needs to be considered.

H₂SiO₃ H⁺ + HSiO₃                                             [4.14]

HSiO; f≡ H⁺+ SiO₃²'                                                   [4.15]

a ₊a             a ₊a ₇

^{h hs,}°³ = ∕ς₁, ^{h si}°³ = κ_a2                                                   [4.16]

^flH₂SiO₃                 ^flHSiO₃

If more than one cation or anion adsorb on the surface, all the possible
reactions need to be considered. Table 4.5 shows equilibrium constants of
different species in bulk solution ^{[24L [25]}.

The ionic strength of synthetic brine is 0.0478 M. For nonionic solute (e.g.
H₂SiO₃), the concentration is low enough to Considerthe activity coefficient as 1.0.
But for ions, the activity coefficients need to be calculated using extended

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