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- Posts: 21
- Joined: Thu Mar 22, 2018 3:56 am
I have a question about ghost peaks in a solvent blank which only appear in one single run (so far) and are relatively sharp. Can I reasonably believe that they are very late eluting compounds from previous samples rather than some kind of contamination upstream of the column?
I have attached the chromatogram where it appeared (in blue).
The solvent blanks are MTBE, analytes are volatile fatty acids, samples are wastewater after liquid liquid extraction into MTBE. Injection volume 1 uL splitless, inlet temp 240C, detector is FID.
None of the samples ran after that one had any ghost peaks. The ghost peaks came out after all analyte peaks and they came out at the maximum isothermal temperature of the column (Restek Stabilwax-DA with a polar deactivated guard column).
I did previously attempt water injections on the same instrument but never exceeded the liner volume and all liner/o-ring/septum have been changed since then.
Please let me know whether this could be a problem or just carry over from late eluting compounds! Thank you!