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Chemical/Petrochemical
Sulfinert@·Treated Sample Cylinders
Store Active Sulfur Compounds at ppb Levels
by NeilMosesman, Air SamplingProducts Manager
• Stable storage of sulfur compounds at ppb levels.
• O.O.T. rated to 1800psi at room temperature.
• High quality cylinders manufactured by Swaqelok ",
Refinery and natural gas samples often contain trace amo unts of sulfur-con­
taining compo unds which can inte rfere with reactions or poison catalysts in
petrochemical processes. Because sulfur compounds quickl y react with stain­
less steel surfaces, accura te determ ination of these compo unds is imp ossible
when samples are collected and stored in untreated sample cylind ers. Restek's
Sulfiner t'" passivation technique bond s an inert silica layer into the surface of
stainless steel, prevent ing active compounds from reacting with or adsorbing
to the steel.
To characterize Sulfiner tv surfaces, we tested the stability of 17ppbv standa rds
of sulfur compounds in three Sulfiner tv sample cylinders over a 54-hour peri­
od. Dimethyl sulfide, which is not adsorbed by stai nless steel, was used as an
internal standar d.
The Sulfinert's-treated cylinders were inert to the reactive sulfur compounds
over the 54-hour test period (Figure 1). Hydrogen sulfide exhibited greater
than 85% recovery; methyl mercapt an, ethyl mercapt an, carbo nyl sulfide, and
dimethyl disulfide exhibited greater than 90% recovery.
Sulfiner t's-treated gas sampling equipment is ideal for collecting and storing
samples containing ppb levels of sulfur compounds, such as natural gas or
beverage-grade carbon dioxide. Sulfinerre treatm ent ensures that sulfur com­
pounds or other highly active compo unds remain stable during tran sport
from the field to the laborator y.
Sulflnert" Treated SwagelokGl Sample Cylinders
These cylinders are made from 304 grade stainless steel with 1/," female NPT
thre ads on both ends.
Size qty. cat# price
75cc ea. 24130 $202
150cc ea. 24131 $228
300cc ea. 24132 $233
500cc ea. 24133 $258
1000cc ea. 24134 $430
2250cc ea. 21394 $829
Sulfinert" Treated Alta-Robbins Sample Cylinder Valves
• All wetted parts Sulfiner rs treated for inertn ess.
• Compa tible with Sulfinerre treated Swageloke sample cylinders.
• Large, durable, Kel-F®seat ensures leak-free opera tion.
Description qty. ca\.# price
'1."NPTExit ea. 21400 $177
'1."Compression Exit ea. 21401 $177
'I'" NPT with Dip Tube* ea. 21402 $253
'I." NPTwith 2850psi Rupture Disk ea. 21403 $354
'1." NPTMaleInlet x '1."FemaleOutlet With 2850psi Rupture Disk ea. 21404 $354
* Specify dip tube length or % outage when ordering(maximum length = 5.25"/ 13.3cm)
2006.03 • 21 •
Figure 1 Stability of sulfur compounds is
remarkable in Sulfinertv-treated cylinders.
120 .,.""=== = = ===--..-,,-,,
~ loo -+~=~~F;=;:~=;;:;;;;;;!i
~ ~
8 80- ------------------~-------
:" Hydrogen Sulfide
120.,.""= - =
10 20 30
time (hours)
40 50
..-,,-,,
60
~ 100 ~cJ=:;;;~~~;:;;:=:::~~
~ 1
:3 80 --------.-.------------- -------------e
Carbonyl Sulfide
10 20 30 40 50 60
time (hours)
120~~~
~ 100
~
:3 80· ----------.--.-------.-------:"
Methyl Mercaptan
10 20 30 40 50 60
lime(hours)
120..,.,.,,==== _ = __= --,
10 20 30 40 50 60
lime (hours)
120 -e-t- --_-- ---,
~ i 100 !,..,.- ,~'"' ,... ""IiII
8 80 -----._---------------------••-----:"
Dimethyl Disulfide
10 20 30 40 50 60
time (hours)
.. Sulfinert" Sulfinert" • Sulfinert"
III cylinder 1 • cylinder 2 cylinder 3
rest ek innovation!
Sulfinert"treatedsampling apparatus.
Sample Cylinder
(cat. # 24133)
Cylinder Valve (cat. # 21400)
Rupture Disc Tee (cat. # 21396)
For Sulfinert' treated fittings, tubing, andsampleloops, refer toour
catalog or visitour website.
for more info
For informationabout Restek surface coatings, pleasevisit
800-356-1688.
Website : E-mail : TelNo : 03 9762 2034 . . . in AUSTRALIA