max column temperature

[Ostwald]

Should the oven's max temperature be set to somewhat below the maximum temperature of the column? Or is it ok to have the maximum oven temperature equal the maximum column temperature in a routine method?

[chromatographer1]

There are TWO maximum column temperatures.

The first is the maximum ISOTHERMAL oven temperature.

The second is the maximum PROGRAMMED oven temperature which is not held but immediately drops after reaching that temperature.

However, asking what maximum temperature a column should be exposed to is like asking the question:

"How hard should the chemist be hit in the stomach? Hard enough to JUST BARELY kill him(her), or just a little bit less than that?"

Temperature damages the phase of a column. Less damage is better. More damage means buy a new column sooner. A higher temperature means that the time to spend becomes shorter, sometimes a LOT shorter.

"Drive at your own risk." "Your mileage may vary." These truisms contain truth. Maximum temperature is a judgment call. LESS is MORE.

best wishes,

Rod

[Peter Apps]

Another thing to keep in mind is that oxygen and water in the carrier gas, and to a lesser extent muck in the samples are what do most of the damage at high temperature. So if your carrier gas is very clean (which costs money) you can save money on columns, or run them hotter and faster.

Your call

Peter