When the reaction
was performed for 3 h at 200 °Cwith the NaOH loading of 0.4 wt.%,
the esterification (%) soared from 81.9% to 98% with the increase of
molar ratio of glycerol to FFA from 0.8:1 to 1.1:1, and it plateaued at
99.5% when the mole ratio of glycerol to FFA is 1.3:1.