7890 dual channel

Hi cmorrow,

I have updated the tags for better visibility .

James

Gasoline Range Organics or Diesel Range Organics? Are you looking for method acquisition parameters or quantitation database help? Also what version of acquisition and quantitation software are you using?

what type of Chemstation software are you using? Is this dual channel confirmation quantitation or 2 different samples injected at the same time?

Thanks Ron,

DRO/MO (C10-C40).

Method parameters Using 30m/0.25mm HP-5MS Sil, with dual FID, MMI final

extraction solvent DCM.  Wanting to do micro-extraction and get away from

doing Continuous Liquid-Liquid.

Thanks,

Charles

We are using EZChrom and two separate samples, so as to increase throughput

and to limit solvent use.  7890A/7683/7683 ALS with dual FID.

Thanks,

Charles

Hi Charles,

Have you looked at US EPA 3511? https://www.epa.gov/sites/production/files/2015-12/documents/3511.pdf

It uses 40mL EPA sample vials with a single in-vial extraction of 35mL of water with 2mL of DCM. Other suitable solvents like hexane or pentane can be used. I did a fair bit of work in the 1980s using similar methods and similar volumes with similar single extractions. Solvents that worked well were Freon 113 (Pre Montreal protocol!), DCM, pentane, hexane, CS2, and CCl4. I used cool Grob on-column injections of up to 10µL on GC-FID and GC-SectorMS instruments, and later a PTV. Some of the work was on GROs with the volatile solvents, but mostly diesel/lubricating oil with Freon and DCM. We also went up to C60+ with CS2 with GC-FID.

US EPA 3570 is a generally similar micro-scale method for soils etc: https://www.epa.gov/sites/production/files/2015-07/documents/epa-3570.pdf As you are are looking at C10-C40 the potential loss of volatiles is less important and you should not need the KD concentration in 3570.

Regards,

Tim