Chapter 5
Before adding NaOH (-10 min, pH 8.5)
Adding NaOH (0 min)
10 min after adding NaOH
• ∙r
30 min after adding NaOH
60 min after adding NaOH (pH 9.5)
(The scale bar is 20 μm)
Figure 5.3 Clay solids skins with time when increasing pH from 8.5 to 9.5
Figure 5.4 shows photographs of the five samples after one day. All of them
have a layer containing oil on the top and a solids layer at the bottom. The
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