Читать книгу Process Gas Chromatographs - Tony Waters - Страница 69

Looking back at Figure 2.9, why is the propane peak exactly halfway along the column? Think about it.

Taking the question one stage further: What would have to happen for another peak to be at a different location in the column, separated from the propane peak?

Simple explanations of gas chromatography often say that different peaks move at different speeds and come out of the column at different times. While this is empirically true, it's a circular argument and explains nothing. It's plainly true that if the peaks come out of the column at different times they must be traveling at different average speeds, but it's illogical to then conclude that the peaks are separated because they move at different speeds. It doesn't explain anything.