The name is absent

Chapter 4

Figure 4.7 shows water-wet fraction of 1.0 w.% kaolinite in toluene-brine
mixture (1:1, v∕v) adding different amounts of CsTAB at pH 8.3 24 hours after
preparation, without naphthenate added. In the figure, water-wet fraction of
kaolinite decreases as CsTAB concentration increases. This reveals that adding
CsTAB only makes kaolinite more oil-wet. Cationic surfactant CsTAB can interact
with negatively-charged groups, for instance, negatively-charged sites on kaolinite
surface or with naphthenate. In the absence of naphthenate, CsTAB will adsorb on
the surfaces of kaolinite with negatively-charged sites and make these surfaces
more oil-wet. Ifthe system contains naphthenate, C₈TAB will interact preferentially

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