Results and discussion
3.1. Phase behavior of palm oil and relation to oil extraction
From preliminary studies, the mixed surfactant system of both
extended anionic Alfoterra145-5PO and Alfoterra145-8PO and
nonionic Comperlan KD were able to form microemulsions with
palm kernel oil at the concentration (wt%) ratio of anionic to
non-ionic equal 0.1–3.0. Therefore, two systems were selected;
System A (Mix 3% Comperlan KD and 0.1% Alfoterra145-5PO)
and System B (Mix 3% Comperlan KD and 0.1% Alfoterra145-8PO)
were scanned with different NaCl in the range of 0–20 wt%. The
interfacial tension was then measured to evaluate phase transition
of the two systems. The results (Fig. 1) show that both extended
anionic surfactants mixed with the non-ionic surfactant in salinity
scans systems generated microemulsion phase transition. The IFT
values of systems with different salt concentrations varied from
1 to 10−3 mN/m. IFT values in the range of 10−2 to 10−3 mN/m are
considered ultralow and desirable. Thus, microemulsion formation