The name is absent

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+σ_d=Q, σ₀=-σ_d

[4.5]

σ₀=-sιgn(σ₀){2^Γ∑ς⁰[exp(-z_ι<∕^)-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 a_s is different from the bulk ion activity að,

α_j(M^z')=α_fr(M^z')exp(--4^
kι

[4.7]

a_s and a⅛: activity at surface and in the bulk.

112