Chromatography Forum

I'm sure there are several conversations regarding GC Column bake-outs already on here so if I can be pointed in their direction I would appreciate it greatly.

I'm running 2 Varian CP-3800 gas chromatographs both with Front TCDs and Middle FIDs. I typically run natural gas samples from oil/gas wells.

I need to do a bake-out on both machines but don't have a method for either that will work at this time. I understand methods but am not positive how to find the temps I need to use that will work without damaging my machines.

I apologize if I'm a little slow in answering replies. Thank you all in advance.

James RH

Every column comes with a specified maximum temperature on its box.

Make sure you don't have leaks and stay for a couple of hours at or below that temperature. You could create a method for it, but it's easier to just use the control panel of the GC when it's not running samples.

The fact that you are analyzing Natural Gas and have multiple detectors on your GC, suggests that you have multiple columns in the oven. Usually, one of the columns used in Natural Gas analysis is a Molecular Sieve column, and this type of column needs to be conditioned at around 350°C, which is way above the max temperature of most other columns. This means that you cannot condition this column in the GC while the other columns are installed.

Gasman

I appreciate your replies. I inherited these chromatographs and will have to search through a lot of paperwork to figure out where the original specs are for these columns.

Also, I do believe there are Mol Sieve columns in these machines. Again, I will have to verify that but I did here them referenced while I was being trained.

Unfortunately, my very experienced boss/trainer ended up retiring a year earlier than expected and now I'm running almost more samples per month than he ran in 2 while trying to play catch-up on my education.

Again, I appreciate all information anyone can give me from here. Thank you.