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Our 20-page technical guide describes the
components of a passive sampling train, and
presents procedures for sampling, for cleaning,
and for certifying the sampling train and canister.
Request lit. cat.# 59977A.
• 13 •
2003 Volume 3
800-356-1688
SilcoCan™ Canisters
Ideal for Low-Level (1ppb-20ppb)
Reactive Sulfur Compounds
Reference
1 Stability study of Low-Level (1ppb-20ppb) Reactive Sulfurs in SilcoCan™ Canisters. Restek Corporation, 2001.
Available on request: lit. cat.# 59347.
SilcoCan™ Air Sampling Canisters
SilcoCan™ Canisters with
Vacuum/Pressure Gauge
volume qty. cat.#
1L ea. 24112
3L ea. 24113
6L ea. 24114
15L ea. 24115
Feature
High-purity, 2 ⁄3-turn valve with stainless steel valve diaphragms.
Vacuum/pressure gauge (optional).
Variety of sizes.
Temperature stability to 250°C.
Silcosteel® valve available (add suffix “-650” to cat. #).
No sample adsorption, for more accurate results; easy to use.
Silcosteel® coated. Inert surface, ideal for containing low-level sulfur compounds.
Indicates internal conditions.
Meet extensive range of sampling needs.
Can be cleaned at higher temperature, producing a cleaner can.
Completely passive sample pathway ensures sample stability.
Analysis of low-level sulfur volatile organic com-
pounds (VOCs), such as hydrogen sulfide (H2S),
methyl mercaptan (CH3 SH), ethyl mercaptan
(C2 H 5SH), and dimethyl disulfide (CH3 SSCH3 ) is
important because of health concerns and odor
complaints near manufacturing sites and refineries.
Collection and measurement of these compounds in
the atmosphere is very difficult because of their low
concentrations and high reactivity. Sulfur VOCs can
react not only with each other, but also with the
Benefit
vessels in which they are collected. This causes low
recoveries. SilcoCan ™ air monitoring canisters,
which feature a Silcosteel®-treated surface, ensure
stability of low-level sulfur VOCs.
We evaluated the stability of sulfur VOCs in
SilcoCan™ canisters at very low levels (1–20ppbv)
for six days.1 Comparison of dry vs. humidified
standards demonstrates the ability of SilcoCan™
canisters to store low-level sulfur VOCs in real-world
conditions (Figure 1). Electropolished canisters
allowed rapid degradation of hydrogen sulfide,
methyl mercaptan, and ethyl mercaptan during a
similar study.
When you need to perform sensitive air monitoring
analyses for sulfur VOCs, use SilcoCan™ canisters to
collect and store your samples.
Rtx®-1, 60m, 0.53mm ID, 7.0µm (cat.# 10193)
GC: Agilent 5890GC
Det.: Sievers Model 355 SCD
Oven Temp.: 30°C (hold 1.0 min.) to
180°C @ 10°C/min. (hold 5 min.)
Flow Rate: 8.5mL/min.
Sample: 1mL (sample loop)
Standards: 2mL of 100ppm stock sulfur standard added to each precleaned and evacuated canister, then pressurized to 30psig with ultra-pure nitrogen.
The resultant concentrations are listed in Applications Note #59347. Humidified standards made by injecting evacuated canisters with 100µL of deionized
water prior to adding 2mL aliquot of stock standard (50% RH).
Dry SilcoCan™ (n=18)
Humidified SilcoCan™ (n=5)
Electropolished canister (n=2)
●
◆
▲
Figure 1 - SilcoCan™ canisters effectively store low-level organic sulfur compounds under real-world conditions.
Time (Days) Time (Days)
Percent Recovery
Percent Recovery
2 H S
1L ea. 24116
3L ea. 24117
6L ea. 24118
15L ea. 24119
By Donna Lidgett, Air Sampling Products Marketing Manager
✔ Stable, long-term storage of sulfur volatile organic compounds.
✔ More accurate data than with electropolished canisters.
Percent Recovery
Time (Days)