Attaching a Packed column to a split/splitless injector.

[Vox]

How exactly do I go about attaching a Packed column to a split/splitless inlet on an HP 5890?

Thanks for any help you may have to offer. I'm really finding this forum quite helpful.

[GasMan]

Vox,

The inlet was never designed to work with packed columns and I am sure that many people will ask why you need to do this. All of the flow control in the column assumes that you have a capillary column, not a packed column. It is possible to mount a 1/4 inch column into the inlet ( without a liner ), but the inlet would then not be acting as a splitter.

Gasman

[GOM]

Vox,

I still have some applications which are actually better run on a packed column and I have just added a packed column inlet and FID to a 6890. You could do the same with your 5890 or find a capillary equivalent for your analysis.

Regards,

Ralph

[AICMM]

Vox,

Your split/splitless inlet is designed to be back pressure regulated which is why it won't work for a packed column. If you have a forward flow controller or pressure controller then the modification of you inlet is pretty straight forward. Plumb a pressure/flow controller in to you carrier supply line, then cut and cap your septum purge line on the weldment, then cap your split vent line. At this point, your injection port is a glorified heating block. Then you install packed column directly into injection port. A friend of mine did this a long time ago but I am not sure I would follow in his footsteps. Tell us again why you need a packed column???...

[Consumer Products Guy]

I've done exactly this on a 5890 Series II GC, similar to what AICMM states. My old 5840 had a split/splitless inlet whiched used the 7671 autosampler, so we set that up like this when we needed to use a packed column. That GC is not EPC-controlled. We use a standard 5890 1/4 inch SS liner which has a 1/8 inch swage thread for the 1/8 inch column to attach. Instead of relying on just an O-ring to hold the liner in place as Agilent states, I bought a spare metal "nut" (the same one that would hold the inlet gold seal if one was using capillary columns) and cut the end off with a hacksaw. I use this to hold the liner in place securely. Why packed? I find it works better for fatty acid methyl esters, so I don't need to use a split injection.