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High-pressure sample cylinders are commonly used for collecting and storing
refinery and natural gas samples containing trace amounts of sulfur com-
pounds. These highly active compounds degrade very rapidly in stainless steel
sample cylinders, making accurate determination of sulfur compounds virtu-
ally impossible. Restek’s exclusive Sulfinert® surface treatment eliminates the
reactivity of high-pressure sample cylinders and allows collection and stable
storage of sulfur compounds, even at ppb levels. Figure 1 shows the recovery
of 17ppbv hydrogen sulfide, carbonyl sulfide, methyl mercaptan, ethyl mer-
captan, and dimethyl disulfide after 60 hours of storage in a Sulfinert® treat-
ed sample cylinder. The data show that these active compounds were unaf-
fected by long-term storage in the Sulfinert® treated cylinder.
In addition to Sulfinert® treated cylinders, we also offer Sulfinert® treated
valves, tubing, and sample loops to ensure the entire sample pathway is inert.
Custom treatment is available for a wide range of items.
Improve Storage Stability for Sulfur Compounds
Using Sulfinert® Treated Sample Cylinders
By Neil Mosesman, Air Monitoring Product Marketing Manager
• Eliminate sample-surface reactions in sample cylinders, collect and store active compounds.
• Obtain accurate data for active sulfur compounds at ppb levels.
• Many treated system components available from stock.
Figure 1
Active sulfur compounds are
stable in Sulfinert® treated sample cylinders.
■
Sulfinert
®
cylinder 3
●
Sulfinert
®
cylinder 2
▲
Sulfinert
®
cylinder 1
Methyl Mercaptan
120
100
80
0
0
10
20
30
40
50
60
●
▲
▲
■
■
time (hours)
recovery (%)
Carbonyl Sulfide
120
100
80
0
0
10
20
30
40
50
60
●
●
▲
▲
■
■
time (hours)
recovery (%)
Hydrogen Sulfide
120
100
80
0
10
20
30
40
50
60
●
●
▲
▲
■
time (hours)
recovery (%)
0
Ethyl Mercaptan
120
100
80
0
0
10
20
30
40
50
60
▲
▲
■
time (hours)
recovery (%)
■
Dimethyl Disulfide
120
100
80
0
0
10
20
30
40
50
60
●
■
time (hours)
recovery (%)
▲
■
●
●
●
●
●
●
●
●
■
▲
●
for
more
info
Please request Applications Note #59164B for more details
about storing sulfur compounds in Sulfinert
®
treated cylinders.
Sulfinert®-Treated Sample Cylinders
• Stable storage of low concentrations of sulfur compounds.
• D.O.T. rated to 1800psi at room temperature.
• 316 stainless steel,
1
/
4
" female NPT threads on both ends.
Size
qty.
cat.#
price
75cc
ea.
24130
$200
150cc
ea.
24131
$225
300cc
ea.
24132
$230
500cc
ea.
24133
$255
1000cc
ea.
24134
$425
2250cc
ea.
21394
$820
Sulfinert®-Treated Sample Cylinder Valves and Rupture Discs
• All “wetted” valve parts are Sulfinert®-treated.
• Maximum pressure rating, 5000psi.
Description
qty.
cat.#
price
1
/
4
" NPT Exit, Kel-F
®
Stem Tip
ea.
24127
$175
1
/
4
" Compression Exit, Kel-F
®
Stem Tip
ea.
24128
$175
1
/
4
" Female NPT Outlet (built-in rupture disc)
ea.
21395
$420
Sulfinert®-Treated Gas Sample Loops
• Ideal for samples containing low concentrations of sulfur compounds.
• Sizes from 5µL to 5cc.;
1
/
16
" fittings, for “W Type” valves.
Size
qty.
cat.#
price
5µL
ea.
22840
$115
10µL
ea.
22841
$115
20µL
ea.
22842
$115
25µL
ea.
22843
$115
50µL
ea.
22844
$115
100µL
ea.
22845
$115
250µL
ea.
22846
$115
500µL
ea.
22847
$115
1cc
ea.
22848
$115
2cc
ea.
22849
$115
5cc
ea.
22850
$115
17ppbv each compound