the Ultrol L70 surfactant at 12 wt%, in which the crude oil was
more easily solubilized. Fig. 4a–c show a photo of the nanoemulsion
containing crude oil, the oil droplet size distribution curves
and optical micrograph, respectively. The graph in Fig. 4b shows
that the size distribution curve is similar to the curve of Fig. 1b
(pure nanoemulsion), indicating no significant change in the
droplet size of nanoemulsion with solubilization of crude oil in
the nanoemulsion. The optical micrograph in Fig. 4c shows the
droplets of nanoemulsion containing crude oil.
The optical micrographs shown in Fig. 5 indicate the onset of
saturation at a concentration of 10 wt%, in which the droplets size
exceeds the ceiling (6000 nm) of the Zetasizer Nano ZS equipment
and the droplets begin to lose their spherical shape but not yet
showing visual phase separation of the nanoemulsion.
The study of the solubility of crude oil dispersed in synthetic
oily water by addition of the nanoemulsion showed that for al