An absolute mean error of 5% has been always observed by computing
the overall mass balance for the multi-component liquid
mixture (palm fatty acids distillates) under investigation. This is
due to losses in the feed pump as well as losses during the liquid
draining in both the extract and raffinate. As a consequence the
mass fractions of all the components of palm fatty acids distillates
in feed, extract, and raffinate were normalized in order to minimize
the component losses. This problem turns to be more complicated
when performing the mass balance of the individual components.
An absolute mean error of 12% for the fatty acids and 15% for squalene
has always been observed after calculating the mass balance
for all the components of palm fatty acids distillates. In the case of
fatty acids, no satisfactory reasons could be found to explain fatty
acids losses except the errors related to the overall mass balance
and chemical analysis, as the fatty acids should not degrade at the
operating conditions used to carry out extraction experiments and
no reaction takes place. Since the formation of new compounds has
not been detected in the gas chromatogram,the hypothesis of reaction
should be discharged. In the case of squalene, the low initial
content in the multi-component feed mixture might be responsible
for the differences on the overall mass balance of squalene.
This may be due to the fact that traces of squalene in the raffinate
could not be detected in the gas chromatogram. For the design and
development of industrial multistage gas extraction processes, all
the aspects concerning possible parallel reactions, degradation, and
interactions with the packing surface must be carefully analyzed.