for temperatures higher than 60 C, the
conversion decreased. This behavior has also been observed in
transesterification reactions using conventional catalysts, such as
sodium hydroxide [33] and methoxide [34]. At lower temperatures,
the reaction rate is slow, thus leading to lower conversion
at a given reaction time. On the other hand, when temperature is
increased above 60 C, the methanol concentration in the liquid
phase is too low to compensate the higher kinetic constant. This
leads to a lower reaction rate and to samples with lower conversion
values.
3.2. Purification stage. Saponification