The name is absent

Chapter 4

4.3.5. Model parameters evaluation and experiment data correlation

In order to correlate zeta potentials of kaolinite in synthetic brine, parameter
values in the model are required. In synthetic brine, the effects of pH, SO4²∖
НСОз’, Ca²⁺ and Mg²⁺ need to be considered. Since Na⁺and CΓ are indifferent
ions, zeta potential measurements of kaolinite in NaCI brine or de-ionized water
with different cations and anions are performed to obtain parameter values in the
model.

4.3.5.1. Surface site density and dissociation constant

To get surface site density and dissociation constants, zeta potentials of
kaolinite in 0.05 M NaCI brine (the ionic strength is close to that of synthetic brine)
at different pH were measured. Here HCI and NaOH were used to adjust the pH.
Equations for charge density and site dissociation equilibrium of kaolinite are:

σ₀ = e([ AlOH₂ ] - [A1O' ] + [SiOH₂ ] - [SiO' ] - [B^ ]) [4.19]

[AlOH]⅝(H*)exp(⅛

[AlOH,] =---------------U- [4.20]

ʌʌl+

[A10]¾(H∙)exp(-⅛

[A1OH] =-----------------[4.21 ]

^Al-

[SiOH]¾(H')exp(⅛

[SiOH]] =---------------Œ- [4.22]

ʌsi+

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