PAH, PCB and PCT in Biofuels

[kdamme]

I'm setting up a GC-MS method for PCB, PAH, Lindane and Pentachlorophenol in solid biofuels. I'm now searching for a good reference material with most or all of these components. The matrix can be anything that's used as a biofuel, I prefer something like wood or biocoal. Has anyone a suggestion?

In a later stadium I also want to add some polychlorinated terphenyls to this method on a 30 m 5-ms column. I have searched a little for application notes, but it's not so easy to find one. I wonder if it's possible to get good results with this type of column on the separation of PCT. I suppose that most of them will have a RT that's beyond the "heavy" PCB, but no idea what conditions to use to start from. Again all suggestions are welcome.

Kevin

[tlahren]

I am currently running a list of high molecular weight (High LogP) comounds on a 10m×0.18mm×0.1µm DB5-HTMS column. I have PCB 52, 153, 209, three tetradecachloro terphenyls, decabromodiphenyl ether, and decabromodiphenyl ethane. I run a column flow through a PTV injector of about 1.8 mL/min. I had to use the 0.18mm ID as I did not have sufficient back pressure on the 6m×0.25mm column I was using earlier. I had great chromatography with all compounds on the 6 meter column but now I have to run separate methods for the PCBs and another for the rest of the compounds. I also have a pretty aggressive oven gradient to 320°C.

I think for your application you might do well with a 15m×0.25mm×0.1µm DB-5 with a high flow rate like 1.8 mL/min. The main problem you may see is excessive broadening of the heavier PCTs if you don't have them eluting quickly. It's becomes a trade-off between resolution and sensitivity with these heavy compounds on GC. You probably won't have to worry about thermal degradation on-column like I do with the brominated species. The chloro seem to be quite stable.

I hope this steers you in a good direction. Let me know if I can answer other questions.

Ty