Synthesis Of Palmitic Acid-based Esters And Their Effect On The Pour Point Of Palm Oil Methyl Esters

摘要

The objectives of this research were to synthesis palmitic acid-based esters and to study their effects on the pour point of palm oil methyl esters. Palmitic acid was esterified with six different branched-chain alcohols, namely 2-propano1, 2-butanol, 2-ethyl-1-hexanol, 2-methyl-1-butanol, 2-methyl-1-propanol and 2,2-dimethylpropane-1,3-diol. The purified products were characterized by FT-IR, ~1H-NMR and ~(13)C-NMR. The effect of the six synthesized palmitic acid-based esters on palm oil methyl esters (biodiesel) was later evaluated. The compounds under study were isopropyl palmitate (1), sec-butyl palmitate (2), 2-ethylhexyl palmitate (3), 2-methylbutyl palmitate (4), isobutyl palmitate (5) and 2,2-dimethylpropane-1,3-diyl daipalmitate (6). All of the synthesized compounds were miscible in palm oil methyl esters due to similar polarity of the solute and the biodiesel. The blends of the resultant six ester compounds in palm oil methyl esters were evaluated respectively for their effect on pour point property. The 2,2-dimethylpropane-1,3-diyl dipalmitate was able to improve the pour point of palm oil methyl esters from 12℃ to 9℃ when 5 wt % was added.