Solubilization of methanol and ethanol in palm oil stabilized by medium‐ and long‐chain alkanols

Solubilization of methanol and ethanol in crude palm oil, refined, bleached and deodorized palm oil (RBD PO) and RBD palm olein (PO_L) was studied using medium‐ and long‐chain alkanols (C₄–C₁₂). Ternary phase diagrams were constructed to determine the solubilization (isotropic) region. The results showed that methanol and ethanol are solubilized to a greater extent in an unsaturated palm olein than the saturated CPO and RBD PO in the presence of long‐chain alkanols. The minima of the solubilization curves for dodecanol, decanol and octanol were 27%, 30% and 33% of alkanol respectively in the methanol system, whereas in the ethanol system, the minima for the same alkanols were found at 22%, 24% and 27%. The longer chain‐length alkanol (dodecanol) requires a lesser amount (21% and 32%) to achieve miscibility compared with 53% and 57% for butanol in mixtures containing 70:30 and 50:50 wt ratios respectively. The kinematic viscosity of the isotropic solutions increases with the chain‐length and percentage of alkanols. Solubilization using a PO_L/methanol/butanol system significantly reduced the kinematic viscosity of PO_L from 72.7 mm² s^?1 to the value allowable for No 2 diesel fuel (1.9–4.1 mm² s^?1) or about a 96% reduction from the initial kinematic viscosity of PO_L. © 2002 Society of Chemical Industry