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ANALYSIS OF IMPURITIES IN
ARGON USING COMPACTGC
WITH PLASMADETEK-2
Due to Helium shortage, gas suppliers see an increased request for alternative gases. Their clients demand high purity with exact
specification for various applications like instrumental use and industrial production. Often PDD (Pulsed Discharge Detector) is used
for measuring impurities in bulk gases. But in case of determining the purity of Argon, separation problems arise with this detector
because Helium is used as carrier gas and the bulk Argon elutes close to Oxygen. The Plasmadetek-2 from LDetek offers the perfect
solution here, since Argon is used as carrier gas, and therefore the bulk peak is not seen at all.
Figure 1 shows a two-channel analyser with single Plasma Emission Detector. Valve V1 and Molsieve column analyse H
2
, N
2
,
O
2
, CH
4
and CO in Ar. A second channel around valve V3 is present for analysing CH
4
, CO
2
, N
2
O and Ethane in Ar. For analysis of
impurities in N
2
, a fore-flush column switching option is added to this channel to vent the bulk N
2
. Figure 2 shows the Molsieve
chromagram of an 11 ppm calibration standard. Figure 3 demonstrates the obtained repeatability, which is excellent. Valve V2
combines both channels to a single PlasmaDetect-2 detector, which contains up to four optical sensors for optimal sensitivity for
each individual component, see figure 4. Figure 5 shows the integrated analyser using CompactGC
4.0
.
Figure 2
Chromatogram
Molsieve column
Figure 3 - Repeatability
Figure 4 - programming 4 optical sensors in one PlasmaDetect-2 detector
GLOBAL ANALYSER SOLUTIONS
P.O. Box 2148, 4800 CC Breda, The Netherlands
T: +31 (0)76 5411800 F: +31 (0)842 206757
info@gas-site.comwww.gas-site.com
Figure 1
Analyser diagram
Figure 5 - CompactGC
4.0
Where
innovation
leads to
success
www.
ldetek
.com
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