Figure 4.15 Simplified model of double layer..............................................................112
Figure 4.16 Zeta potentials of kaolinite in synthetic brine with different additives........121
Figure 4.17 Zeta potentials change of kaolinite samples in synthetic brine.................122
Figure 4.18 Zeta potential of kaolinite in 0.05 M NaCI brine at different pH.................125
Figure 4.19 Silica sites fraction in kaolinite at different bulk pH in 0.05 M NaCI..........126
Figure 4.20 Alumina sites fraction in kaolinite at different bulk pH in 0.05 M NaCI......127
Figure 4.21 Zeta potential of alumina in 0.05 M NaCI brine at different pH.................128
Figure 4.22 Alumina sites fraction at different bulk pH in 0.05 M NaCI........................129
Figure 4.23 Kaolinite zeta potential in 0.05 M NaCI brine adding Na2SO4 at pH 6.5 ...131
Figure 4.24 Kaolinite zeta potential adding NaHCO3 in de-ionized water at pH 8.3 ....132
Figure 4.25 Kaolinite zeta potential in 0.05 M NaCI brine adding CaCI2 at pH 6.5......133
Figure 4.26 Kaolinite zeta potential in 0.05 M NaCI brine adding MgCI2 at pH 6.5......134
Figure 4.27 Kaolinite zeta potential in synthetic brine adding NaOH at different pH....136
Figure 4.28 Kaolinite zeta potential in synthetic brine adding Na2CO3, pH 8.3 - 8.9....137
Figure 4.29 Kaolinite zeta potential in synthetic brine adding Na2SiO3, pH 8.3 - 9.0 ...139
Figure 4.30 Kaolinite zeta potential in synthetic brine adding Na4SiO4, pH 8.3 - 9.2 ...140
Figure 4.31 Kaolinite zeta potential in synthetic brine adding Na3C6H5O7, pH 8.3.......142
Figure 4.32 Zeta potential change with different additives in synthetic brine...............143
Figure 5.1 24 h emulsion adding 200 ppm demulsifier PR1 - PR6 at 50 0C................151
Figure 5.2 Photographs of 24 h emulsion with 200 ppm PR5 adding NaOH or Na2SiO3
at different pH..........................................................................................151
Figure 5.3 Clay solids skins with time when increasing pH from 8.5 to 9.5...............154
Figure 5.4 Photographs of 24 h emulsion with NaOH or Na2SiO3 at different pH......155
Figure 5.5 24 h emulsion without changing pH or shaking (Sample 7)......................156
Figure 5.6 24 h emulsion with shaking, without adding NaOH (Sample 9)................157
Figure 5.7 24 h emulsion adding NaOH with shaking (Sample 10)...........................158
Figure 5.8 O∕W emulsions with time when lowering pH from 8.8 to 4.5....................162
Figure 5.9 Photographs of 24 h emulsion samples adding HCI at different pH..........162
Figure 5.10 24 h emulsion adding HCI (equilibrium pH 5.0)........................................162
Figure 5.11 24 h emulsion sample adding HCI (equilibrium pH 6.0)............................163
Figure 5.12 Photographs and photomicrographs of emulsion sample during the whole
operation procedure.................................................................................165
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