Microemulsions (µE) were prepared with palm fatty acid methyl esters (PFAME) as solvents, and stabilized by ethoxylated non-ionic surfactants, i.e., Dehydol LS 7 and Dehydol LS 2 as SA and SB with the hydrophiliclipophilic balance (HLB) values at ~12.8 and ~7.3, respectively. The co-surfactants chosen were 1,2-hexanediol, 1,2-butanediol, 1,2-ethanediol and glycerol. The effects of the co-surfactants on the partial ternary phase diagrams were studied at 10%, 15%, 20%, 25%, 30% and 40% (w/w) concentrations. The ratio of PFAME to water was either 25:75 or 50:50. The mixtures were agitated vigorously, and then kept at ambient temperature (25°C) for one to two days. The emulsions (two-phase), the µE and liquid crystalline phases were observed using polarised light. In addition, the physical stability of the µE solutions was determined at 45°C over a period of one month. The effects of the co-surfactants on the ternary phase systems for PFAME/non-ionic surfactants/water were studied and mapped out at 25°C and 45°C, respectively.
Author Information
* Malaysian Palm Oil Board,
P. O. Box 10620, 50720 Kuala Lumpur,
Malaysia.
E-mail: ismail@mpob.gov.my
** Faculty of Science and Technology,
Universiti Malaysia Terengganu (UMT),
Mengabang Telipot, 21030 Kuala Terengganu,
Terengganu, Malaysia.
Subscribe with us to get the latest information on Palm Oil Research from MPOB today!