Installation of packed column

[Dominique]

Hi everyone!
I use a 6890N GC, and I need to run a method for terpin hydrate using a packed column with a diameter of 1/8". No packed column has ever been used on this GC, and I have never installed one. Currently we use a split/splitless injector and the FID detector has a capillary jet of 0.29 mm i.d.
The agilent catalog recommends a different injector and detector jet for packed columns, but do I absolutely need to change both of them? Or if I find a way to adapt the column, this would be enough? The problem is that getting the parts would probably take some time, and the analysis is being needed....
One more thing, the coil diameter of the column we got is such that the ends of the column don't reach the injector and detector. Could it damage the column if I try to uncoil it myself... with my bare hands???
As you can see, I seriously need some help...!
Thanks...
Domi

[Consumer Products Guy]

Hi everyone!
I use a 6890N GC, and I need to run a method for terpin hydrate using a packed column with a diameter of 1/8". No packed column has ever been used on this GC, and I have never installed one. Currently we use a split/splitless injector and the FID detector has a capillary jet of 0.29 mm i.d.
The agilent catalog recommends a different injector and detector jet for packed columns, but do I absolutely need to change both of them? Or if I find a way to adapt the column, this would be enough? The problem is that getting the parts would probably take some time, and the analysis is being needed....
One more thing, the coil diameter of the column we got is such that the ends of the column don't reach the injector and detector. Could it damage the column if I try to uncoil it myself... with my bare hands???
As you can see, I seriously need some help...!
Thanks...
Domi :)

Yes, you can gently stretch the stainless steel column to reach. We currently have a 1/8 column installed in a 5890 split/splitless inlet, very simialr. You'll need a different stainless steel FID liner, and should use a packed-column jet (smaller hole in its "tail" than the capillary jet, as the capillary column goes inside its jet). On the inlet side you'll also need the packed column stainless steel liner, which will attach to your column. This liner will be held in the inlet by an O-ring, like your glass split/splitless liner is when using capillary. That's not the most secure arrangement if you bang the column however; we took an Agilent inlet nut (that goes under the inlet in the oven compartment, drilled it out so the 1/4 inch SS liner would fit through, hacksawed a small amount off its "tail", and used a graphite ferrule to secure the SS liner in place, makes it more sturdy. We also capped off the septum purge vent fitting with a Swagelok cap.

[Dominique]

Thanks for replying so quickly!
Now, please tell me if i understand correctly:
Here i have the diagrams of both the split/splitless inlet and what is called the purged-packed inlet for packed columns, and they have some different parts. But i could make it work if i change to the SS liner and make arrangements to secure the column "as needed"? I wouldn't need a specific adapter?
And for the detector, it's not just the connection itself that i have to change or arrange, but i will also need a new jet (apparently these have a bigger hole of 0.46mm or 0.76 mm). I just want to be sure that i get all the pieces to make it work....
Thanks a lot!

Domi

[GasMan]

First, the 6890 comes with two flavors of flame detector. One is dedicated to be only used with capillary columns, and the other allows adapters to be fitted so that packed or capillary columns may be used. The only difference is the part that comes into the oven and the jets. For the capillary column only version, there is no adapter from Agilent to enable you to connect a packed column. You will have to come up with something your self. If the bottom of the detector has a large external thread, then you have packed/ capillary version. The capillary only version has an internal thread.

The other issue could be using the capillary inlet with a packed column. There will no control of the column head pressure. You have to realise that the capillary inlet controls the flow in the column by pressure via a calculation. You can set the total flow up, and this will be the flow through your column, providing you have the septum purge capped off. If you will be temperature programming, there will be no compensation for flow change in the column. You will need to run in split mode.

Before starting this project you should first consider if there is a possibilty to use a capillary column or megabore column for your analysis.

Gasman

[Consumer Products Guy]

Agilent part numbers added:
Yes, you can gently stretch the stainless steel column to reach. We currently have a 1/8 column installed in a 5890 split/splitless inlet, very simialr. You'll need a different stainless steel FID adapter liner #19231-80520, and should use a packed-column jet #18710-20119 (smaller hole in its "tail" than the capillary jet, as the capillary column goes inside its jet). On the inlet side you'll also need the packed column stainless steel adapter liner #19243-80510, which will attach to your column. This liner will be held in the inlet by an O-ring, like your glass split/splitless liner is when using capillary. That's not the most secure arrangement if you bang the column however; we took an Agilent inlet nut #18740-20800 (that goes under the inlet in the oven compartment, drilled it out so the 1/4 inch SS liner would fit through, hacksawed a small amount off its "tail", and used a graphite ferrule to secure the SS liner in place, makes it more sturdy. We also capped off the septum purge vent fitting with a 1/8 inch Swagelok cap/plug. If I get ambitious and get the time, maybe I can upload pictures of ours. Our 5890s and 6890s have the same FIDs and inlets.

My legal deparment states that you should confirm the part numbers yourself and that our company accepts no liability if you order the wrong part. My Statistics department wants to know how many times I've installed packed columns into a capillary GC, and how many times this was successful. My QA department states: "what's a GC?"

[Dominique]

Hi Gasman,
Thank you.... I would use constant column pressure and temperature, so maybe the pressure control issue wouldn't be such a problem?
I also looked up alternative methods, but they all used packed columns, so i have serious doubts about the use of a megabore column even.

CP Guy: Thanks for the numbers! I hope you get ambitious...

Domi