Extra Peak in Front of methane
Posted: Wed Mar 29, 2017 8:20 pm
We have an FID with methanizer that we are using to analyze CH4 and CO2. Recently we had a large peak start showing up immediately before the normal methane peak that is overlapping and making calculating the methane peak size impossible. We use an autosampling system that runs from our sample bottles to a manifold. The manifold also contains 4 standard gases. None of the standards have this peak. From my research I have found this is most likely oxygen in the system, and does not occur in standards because there is not oxygen. I also read it may be due to carbon build up so I replaced the catalyst and cleaned all tubing. We still have the extra peak and I am totally stumped.