Chapter 4
kaolinite as the function of Na2SO4 concentration in 0.05 M NaCI brine at pH 6.5.
The adsorption constant ∕<s04 is 0.195 m3∕mol.
C(Na2SO4) (M)
x103
Figure 4.23 Kaolinite zeta potential in 0.05 M NaCI brine adding Na2SO4 at pH 6.5
In order to study the effect of bicarbonate, zeta potentials of kaolinite with
different NaHCO3 in de-ionized water at pH 8.3 were measured. In NaHCO3
solution, positively charged sites -AOH2+ can adsorb HCO3^ ion and become
neutral sites -AOH2HCO3.
-AOH2 +HCO3 f≡ -AOH2HCO3 [4.34]
κ _ [AOH2HCO3] [AOH2HCO3]
hc°3 [AOH2]α∕HCO3) [AQH2 ]αz, (HCO3 )exp(-)
131