Chapter 4
Figure 4.15 shows the simplified model of double layer.
Solid
Figure 4.15 Simplified model of double layer
Eqs. [4.1] and [4.4] can be rewritten as:
σ0+σd=Q, σ0=-σd
[4.5]
σ0=-sιgn(σ0){2^Γ∑ς0[exp(-zι<∕^)-l]},z2
[4.6]
Near the charged surface, ion concentration is different from bulk solution
due to the electrostatic attraction or repulsion. From Boltzmann equation, ion
activity near kaolinite surface as is different from the bulk ion activity að,
αj(Mz')=αfr(Mz')exp(--4^
kι
[4.7]
as and a⅛: activity at surface and in the bulk.
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