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- Posts: 44
- Joined: Wed Jul 11, 2012 1:45 am
- Location: California
I'm running EPA 524.2 by purge and trap on a Agilent 5977/7890 with an OI Eclipse 4760.
Our 1,1-Dichloroethene recovery was individually higher than all the other analytes in a recent PE sample.
In the past this has been traced back to the breakdown of 1,1,1-Trichloroethane to 1,1-Dichloroethene in the #10 trap we use, but the breakdown of our current trap is around 2% and since 111-TCA was spiked low in the PE it does not account for very much of the increase.
I was thinking that, perhaps there was some degradation in our calibration standard of 1,1-DCE due to it being mixed with everything else (gas oxygenates, keytones, ...) but I could not find any chemistry that made sense.
To test it anyways I left a mixed standard sealed out at room temperature for a few weeks. 1,1-DCE did not degrade when compared to a paired standard stored at -20c.
Does anyone have any ideas of what could be causing this?
Thank you for any help you can provide.