Analysis methods for carbonyl sulfide
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There are currently several analysis methods for carbonyl sulfide (COS): 1. Analytical instruments, 2. Detection tubes. Are there any other methods?
We generally use gas chromatography with a thermal conductivity detector and a GDX-301 packing column. I haven’t tried other methods.
What type of chromatography? Is it domestic? What is the accuracy?
GC-960 gas chromatograph, from Shanghai Haixin. We have been using it, and its accuracy is fairly good; our detection range goes from a few hundred ppm to 5000 ppm. It is mainly used to detect COS and H2S in raw gas or syngas.
Can the detection range be lowered further? Or replace the chromatography column; our detection range is 0~200 ppm
We use the TY-2000 gas trace sulfur analyzer from the Southwest Institute, with measurement ranges of 0.02–2 ppm and 2–300 ppm.
For concentrations ranging from 0 to 200 ppm, an FPD detector and a capillary column are recommended; domestic brands such as Beifen Ruili or Fulite are also suitable options； Or a PFPD detector ； If funds are sufficient, an ECD detector can be used; it offers the best linear response for detecting trace amounts of sulfur. Specific chromatography columns can be consulted with the chromatography manufacturer. The disadvantage of FPD detectors is their poor linearity and narrow linear range; a standard curve is required when there are significant fluctuations in the components. Regarding the chromatography column: Select the column based on the components to be analyzed. If there are no other substances that could interfere with the main component, in the case of gas, where only H2S and COS are present, a GDX-301 packed column can also be used; however, the replacement time will be longer ； The capillary column requires a small sample volume and has a short replacement time; I can’t remember the specific model. Hope this helps!