Topics Covered
Introduction
PIONA+ Analyzer
Instrumentation used
Results and discussion
Conclusion
About Bruker - Chemical
and Applied Markets
Introduction
Gas chromatography (GC) is highly versatile and widely used
technique for characterizing volatile chemical compounds. It can be
used to quantitatively analyze the types of hydrocarbon (olefins,
napthalenes, aromatics, etc.) in a sample of hydrocarbons, which makes
it very useful for examining fuel compositions.
GC
analyzers from Bruker are configured and tested to exceed
industry
standard performance requirements
for a variety of widely used methods (ASTM, UOP, EN, ISO, GPA).
Available in an array of configurations, Bruker Standard GC Analyzers
utilize the leading analytical performance characteristics of the
Bruker 400 Series of Gas Chromatography Systems.
PIONA+™ Analyzer
The PIONA+
Analyzer from Bruker is especially designed and
configured to be fully compliant with any of the following established
methods including: ASTM D6839, EN-ISO-22854, ASTM D5443, ASTM D1319,
IP-382, IP-526, EN 14157, UOP 870 and DIN-51448.
The PIONA+
uses an automated multidimensional GC approach to analyze
hydrocarbon content by type and carbon number, which allows complete
characterization of a hydrocarbon sample, such as spark ignition engine
fuels,
including individual oxygenates.
The sample is separated in the component
groups per carbon number and in individual components
through the use of multiple columns and traps. In the
PIONA+
system, paraffins, iso-paraffins and iso-olefins,
olefins, naphthenes and aromatics are identified.
However,
analysis time in the PIONA mode is about 180 minutes,
which severely limits the number of samples that can be
analyzed per day. A unique aspect of the design of the
Bruker
PIONA+ Analyzer is the ability to independently heat
the individual traps (concurrent heating). This application
note describes work to determine if concurrent heating
could be used to significantly reduce the analysis time and
improve sample throughput.
Instrumentation used
Results and Discussion
As shown in Figure 1, when the PIONA+
system
is
operated in the conventional mode, a total analysis time
of 180 minutes is required to elute all of the component
groups. However, as shown in Figure 2, through the use
of concurrent heating of both Bruker Molsieve 5A and 13X
traps, a reduction in total analysis time from 180 minutes to
95 minutes is obtained, i.e. ~50 % less.
Figure 1: Chromatogram of a
test sample 1 in conventional PIONA mode.
The reduction in analysis time is achieved by carefully
optimizing the temperature settings of the various traps and
columns and invoking simultaneous heating of the
Molsieve traps. This approach, referred to as the
“FastPIONA” mode, results in the elution of the paraffins
immediately after their naphthene and iso-paraffin
counterparts.
Yet the elution integrity of the component
groups remains intact with no negative influence on either
naphthene or iso-paraffin groups. Figure 3 shows a close-up
of the resulting elution sequence. The same results occur
for the olefin group separations. The cyclic and iso-olefins
normally elute from 100–130 minutes and the n-olefins, in
conventional PIONA mode, from 150–180 minutes.
However, through the use of concurrent heating they
completely elute between 55 and 70 minutes (Figure 4).
In the example of Figure 5, a commercial standard was
analyzed for O-PIONA (oxygenates, paraffins, iso-paraffins,
olefins, iso-olefins, naphthenes and aromatics) utilizing the
concurrent heating approach described above. Note that
the oxygenates elute separately from the other component
groups and are easily identified and calculated by the
PIONA+
software.
Figure 2. Chromatogram of
the test sample in fast PIONA mode.
Figure 3. Close-up view of
C8 and C9 components. Separation in both conventional and fast
PIONA mode.
Conclusion
Temperature programming a Molsieve 5A trap (concurrent
heating) together with a Molsieve 13X trap greatly reduces
the total analysis time for hydrocarbon streams with the PIONA+
Analyzer and, in
some cases, can improve the performance.
Total analysis
time is reduced by one third in the case of O-PIONA and
by as much as half for PIONA. The reduction in analysis
time is possible without any hardware changes and can
be achieved without any negative effect on the quality of
the component class separation. In addition, the analyses
remain compliant with the method EN ISO 22854:2008.
Figure 4. Close-up view of
olefins in conventional and fast PIONA mode.
Figure 5. Chromatogram of a
commercial standard in fast O-PIONA mode.
About Bruker -
Chemical and Applied Markets
Bruker
is the new name in chemical analysis. Accurate and comprehensive
analysis of exogenous and discrete elements in a wide range of sample
matrices are key applications for many analytical chemistry groups. To
address the needs and challenges of analysts working in those areas,
Bruker has expanded their product family to provide, and expertly
support, a series of fully integrated solutions including:
- Gas Chromatography-Mass Spectrometers (GC/MS and GC/MS/MS)
- Inductively Coupled Plasma Mass Spectrometers (ICP-MS)
- Gas Chromatography Systems (GC)
Widely used in food and consumer safety testing, forensic,
industrial, environmental, and clinical laboratories, these systems are
well accepted and established market leaders that universally deliver
outstanding performance at a premium value.
This information has been sourced, reviewed and adapted from
materials provided by Bruker - Chemical and Applied Markets (CAM).
For more information on this source please visit Bruker - Chemical and Applied Markets.