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Benzene in water adsorption test and GC without extraction?

  1. Apr 3, 2015 #1
    Hi all,
    I want to measure the concentration of benzene or toluene, in water with a GC, FID detectors. I put benzene in water with an adsorbent and after hours I've to test the concentration of benzene. In the lab we've already methanol and toluene, so I'm thinking to use toluene as pollutant for the adsorption test and methanol for the calibration. I also have dichloromethane but I probably is too volatile to be suitable. So I want conduct the calibration using only with 1,5,10,100,200 ppm of toluene in methanol..use benzene as internal standard could be suitable? In this way I could test after benzene in water and use toluene as internal standard.
    I don't want volatilisation, but I want to conduct the tests at room temperature. The adsorption test will be in vials closed (by PTFE/silicone septa?), continuously stirred and I want to full the vials with water and toluene, with no headspace. Immediately prior to the GC injection, six times in 24 hours, I want remove the cap and take out half microliter of water from the sample with a syringe, I'll full the other 50% of the syringe with the substance that I've used for the calibration (methanol) and I'll inject all in the GC (with FID detector).
    Finally, I'd like to understand if this is or not a good procedure or if improvement are needed. And also if methanol is ok for my column.
    All advices are welcome!
    My column is capillary, non polar, suitable for aromatics and pesticides. Phase: bonded; poly(5%diphenil/95%dimethylsiloxane).
    Thank you
  2. jcsd
  3. Apr 8, 2015 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
  4. Apr 9, 2015 #3
    All ok, you can remove the post
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