SF6 saturating ECD

I am testing high purity SF6 on our ECD detector to detect/monitor for impurities. Generally, an impurity shows up at 9 minutes RT, while the SF6 peak shows up at around 3.3minutes. I am battling with an issue where the SF6 saturates the ECD, causing the peak at 9 minutes to be hidden by the tail of SF6. We direct the sample away from the ECD until 7 minutes, then direct the sample to the ECD to try to avoid saturation, but the tail of the SF6 peak is still present and it's magnitude is not consistent. We have a partner testing lab who uses this identical method but does not have this saturation problem. Does anyone have any suggestions for troubleshooting/resolution? I'd like to avoid changing the temperature & flow rate as the method is already validated as is.

Parents
  • Hello,

    Since the method works in another laboratory, the issue may not come from the impurity concentration but rather from the ECD source.
    I understand that the parameters are the same for the partner laboratory.

    When was the last preventive maintenance performed on your GC?
    How old is the source?
    What is the current offset signal?

Reply
  • Hello,

    Since the method works in another laboratory, the issue may not come from the impurity concentration but rather from the ECD source.
    I understand that the parameters are the same for the partner laboratory.

    When was the last preventive maintenance performed on your GC?
    How old is the source?
    What is the current offset signal?

Children
No Data
Was this helpful?