decrease in intensity of peaks in varian micro GC
Posted: Sat Feb 26, 2011 9:02 pm
Hello,
We use varian micro GC with TCD detector to detect compounds of hydrodesulphurization. When we used it in July 2010, it was working very well. The intensities of products were much higher and signal to noise ratio was really good.. It was not used for several months afterwards. We have started using it now (feb 2011). I also baked the GC column at column oven temperature of 120 C for a day with N2 carrier gas before starting the latest experiments. But the intensities of our products are really small this time..atleast decreased by 1000 orders of magnitude.. I have no idea why this has happened. Another important question is.. Our carrier gas connection is opened to GC all the time. But the pressure in the cylinder does not decrease . Does GC takes in the carrier gas only when it is working? I do not know.. Please help to solve the problems with intensity and answer the carrier gas question.
Regards
malli
We use varian micro GC with TCD detector to detect compounds of hydrodesulphurization. When we used it in July 2010, it was working very well. The intensities of products were much higher and signal to noise ratio was really good.. It was not used for several months afterwards. We have started using it now (feb 2011). I also baked the GC column at column oven temperature of 120 C for a day with N2 carrier gas before starting the latest experiments. But the intensities of our products are really small this time..atleast decreased by 1000 orders of magnitude.. I have no idea why this has happened. Another important question is.. Our carrier gas connection is opened to GC all the time. But the pressure in the cylinder does not decrease . Does GC takes in the carrier gas only when it is working? I do not know.. Please help to solve the problems with intensity and answer the carrier gas question.
Regards
malli