Chromatography Forum

Hi! I am now doing the CO2 hydrogenation research. I use srigc 8610C to analyse my raw materials and products. CO2 and H2 are the raw materials, and CO, methanol and dimethyl ether are the products. I am trying to use internal standard method, N2 as internal standard. Moleseive 5A column is used to analyse CO, N2, while Porapak Q column to analyse CO2, methanol and dimethyl ether. The GC have a TCD detector and a FID detector equipped with a Methanizer. I bubbled N2 into methanol at 273.15K in order to get the relative response factor.
Here is my question. The peak of methanol appears in both TCD and FID detectors, and the peak of N2 appears only in TCD detector. So which area of methal should I choose for the calculation of Relative Response Factor.
I hope someone can help me with this. Thank you very much!

The 'response factor' is dependant on the chromatographic conditions (in your case the detector). Therefore, the decision is up to you! What do you want to do with the response factor?

The 'response factor' is dependant on the chromatographic conditions (in your case the detector). Therefore, the decision is up to you! What do you want to do with the response factor?

I would like to quantitate methanol through relative response factor

It seems to me, as far as manipulation of the chromatographic data with the response factor goes, you can use the N2 response from the TCD and the methanol response from the FID if you want. You just have to do it the way you choose, all the time. You can't mix your modes. Those particular detectors are not usually subject to a whole lot of drift in my experience.

Generally when you create a standard you have known amounts of your analyte and internal standard in your mixture. By sparging N2 into methanol to get your "standard", how do you know how much methanol is in it at any given time? Intuitively, I'd think that perhaps N2 saturated with methanol would give you a response in the TCD that is in the nonlinear range. The flame might be ok but it might not. Have you checked this aspect of your analysis?