Chapter 4
[AlO⅛(H+)exp(--⅛
[A10H] =-----------------[4.30]
-^Aï-
Figure 4.21 shows the experiment data and fitted curve of alumina zeta
potentials in 0.05 M NaCI brine at different pH. Zeta potential of alumina changes
from positive to negative with the increase of pH. Dashed line shows zero zeta
potential value as reference.
Figure 4.21 Zeta potential of alumina in 0.05 M NaCI brine at different pH
Table 4.9 shows the calculated parameters from data fitting. Dissociation
equilibrium constants and site density of alumina are 4.21 ×10'8 mol∕m3, 3.58×10^1°
mol∕m3 and 1.09×10^7 mol∕m2, respectively. For alumina sites on kaolinite, the
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