Saturated CO2, CH4 measurement with GC

[jojo]

HELLO THERE,
My experiment goes like this. A bottle is filled with 20 ml of distilled water and is rubber tight. the head space consists of mixture of carbondioxide and methane(company made). The mixture of gas is 50% methane and 50% carbondioxide. A 260 ml glass bottle is filled with 20 ml water and tight with butyl robber stoppers and sealed with aluminium cover. Two needles are inserted in the stoppers and are connected by robber pipes. one for the gas in and one for out. The out going pipe is water sealed so that no atmospheric air can get chance of getting mixed. In this way the bottle is flushed with gas for several minutes. finally both needles are carefully removed.
I put the bottles first at 70 degree centrigrade water bath. The GC TCD results shows very much increase increrase in the concentration of both methane and carbondioxide. It shows the increase in methane concentration from 50% to 70% and carbondioxide from 50% to 100 %. Can anyone please explain why this happens.

thank you very much

[Don_Hilton]

I would suggest keeping the thread in one place.

You have answered part of what we need in the student projects thread. We stilll need to know how you are getting numbers (calibration of instrument and reading from the calibration) and how you are taking analytical samples.