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• 4 • 2008 vol. 3
Eliminate Column Breakage in High Temperature
Biodiesel Analysis
Unsurpassed Stability
The high temperature programs required for
analysis of biodiesel oils (B100) by either ASTM
D-6584 or EN-14105 methodology present a sig-
nificant challenge to the analytical column. High-
temperature fused silica tubing breaks down under
these extreme conditions, but the metal MXT®
tubing does not degrade, even at temperatures up
to 430°C (Figure 1). This allows analysts to bake
out any residue eluting after the triglycerides, pre-
venting carryover without damaging the column.
So how well do the MXT®-Biodiesel TG columns
perform? We conducted a benchmarking experi-
ment comparing an MXT®-Biodiesel TG column
with an Integra-Gap™ retention gap to a high-
temperature fused silica column which was coupled
to a conventional 0.53mm retention gap.
Methodology followed ASTM method D-6584,
except the final temperature was modified to 430°C.
Both columns were subjected to 100 temperature
cycles up to 430°C and then derivatized B100 was
injected to check column performance.
This evaluation was performed using a Shimadzu
2010 gas chromatograph equipped with a flame
ionization detector, a model AOC 20i + S autosam-
pler with a 10µL SGE syringe and 42mm 26-gauge
needle, and a cold on-column programmable
injector with a stainless steel injector insert. A
Parker hydrogen generator supplied the carrier
gas. Peak symmetry and retention time were evalu-
ated as indicators of thermal stability.
Peak symmetry of butanetriol on a commercial
high-temperature fused silica column deteriorates
after just 20 injections, compared to the excellent
symmetry that is maintained on the MXT®-
Biodiesel TG column (Figure 2). In addition to peak
shape, retention time stability was used to evaluate
column performance. The decrease in retention
time seen on the high-temperature fused silica col-
umn indicates the liquid phase is being lost
(Figure 3). In contrast, the consistent retention
times obtained on the MXT®-Biodiesel TG column
demonstrate its stability. Practically, this translates
into reliable performance and longer column lifetimes.
MXT®-Biodiesel TG columns
are undamaged by the high
temperatures required for
biodiesel analysis and easily
outperformhigh temperature
fused silica columns.
thank you
Instrument provided courtesy of Shimadzu
Figure 1 MXT®-Biodiesel TG columns are undamaged by high
thermal cycles compared to high-temperature fused silica
columns, which break down under the same conditions.
100 temperature cycles to 430°C totaling 500 minutes at maximum temperature.
Figure 2 Stable and consistent peak shape for the internal standard
butanetriol gives you more accurate quantitation.
Figure 3 Retention time is stable on a metal MXT®-Biodiesel TG
column, even after 100 cycles up to 430°C.
MXT®-Biodiesel TG
columns are
undamaged by
high thermal cycles.
HT fused silica
columns, labeled
as stable to 430°C,
show pitting and
breakdown.
More stable than
fused silica!
Chemical/Petrochemical
800-356-1688 •