Now that the system
is calibrated, prepare
an actual BioDiesel
sample by placing
100ul of BioDiesel,
100ul of Tricaprin in
pyridine, 100ul of Bu-
tanetriol in pyridine,
and 100ul of MSTFA
in a vial. Allow 20
minutes for the reac-
tion then dilute to 8ml
with heptane.
Inject 1ul to generate
a chromatogram simi-
lar to the one at the
right
Zoom in to the region
surrounding themono,
di and triolien. Stretch
the total mono, di and
tri component window
so it includes the
small peaks surround-
ing themonoolien, di-
olien and triolien. The
ASTM 6584method
does not precisely de-
finewhich peaks to
include or exclude, so
there is some judge-
ment required on the
part of theoperator.
PerformingASTM6584 freeand total glycerin in
BioDiesel usinganSRI GasChromatograph
andPeakSimple software version3.67
Themainbiodiesel esters are the very largepeaks
in this regionof the chromatogram
Thepeaks surrounding themonoolienare
assumed tobeothermonoglycerides
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