Cresol/Xylene analysis by GC/FID...need help

[Roehrs]

Hi!
I have to analyse cresol and xylene by GC/FID and splitless injection mode. I use an HP-INNOWax (PEG) column.

Can you send me a good method for the analysis?

What is the best temperature programmation for? And which solvents and internal standard can I use?

Thank you!

[chromatographer1]

Generally beginning at 60°C and programming the oven at 4°C until your peaks elute will work.

Almost any solvent is recommended except water or methanol.

I would not use an injector, column oven, or detector temperature far above 200°C to avoid damaging the column.

good luck and best wishes,

Rod

[Consumer Products Guy]

Use a carrier gas oxygen trap with PEG columns.

[Roehrs]

And which internal standard is good for the method?

[chromatographer1]

The internal standard should chemically be similar to the analytes you are measuring.

In your case diethylbenzene? Cumene? Even Toluene?

You could also use a simple alkane if that is all you have available.

best wishes,

Rod

[Roehrs]

The producer of the column wrote me that I can use any solvent I want. Also water and methanol! So, the best choise would be water as solvent.

What do you think about it?

[chromatographer1]

I would NOT use water or methanol if possible. Ether would be a possibility if you need to make sure any trace water is dissolved.

I would also avoid acetone but might consider 2-butanone.

I WOULD USE

any hydrocarbon, aromatic, or chlorinated hydrocarbon solvent.

For example: pentane, hexane, heptane, tetraethylbenzene, methylene chloride, chloroform, etc

Be certain that cresol and xylene do not coelute with the solvent you pick.

best wishes,

Rod