Aromatic in carbon black

[laucc]

Can anyone provide me some info on how to determine aromatic in carbon black using gc/gc-ms? Thanks in advance.

[Schmitty]

PAHs?

-extract with 99.9% toluene
-rotory evap to concentrate
-inject vs. standards (gc ramp 40 to 300C)

[laucc]

Thanks Schmitty, can you provide a more detail procedure. And what if i need to get the saturated as well? Many thankx

[Schmitty]

I haven't analyzed straight-chain saturated hydrocarbons in conjunction with PAHs.

The method I used is proprietary, but it essentially consists of:
-refluxing or soxhleting the carbon black
-filter/separate
-concentrate to a final volume
-inject on GC/MS with reference standards in toluene with a normal temperature program.

You can add the sat hydrocarbons to your standard mix, and see through validation if they are recovered acceptably. I also recommend using the highest purity toluene possible, to avoid interference. I was having problems with a standard at 1ppb with anything other than 99.9% toluene.

Hope this helps.

[laucc]

Thank you Schmitty