How should I store my GC column?

GC Column Storage

We (tech service) often get asked about storage conditions of our GC columns. We thought the blog may be a good venue to revisit this topic. To simplify this information, it may be best to provide three different time-frames:

1)  Overnight: Our recommendation if using a column daily is to leave the carrier gas on overnight and set the GC oven temperature to 110°C. This prevents water vapor from condensing inside the column and minimizes the time before the column is ready to use the following day.

2)  Up to one week: This is considered the transitional time-frame since depending upon the specifics of your carrier gas flow rate, column, detector, and analysis, it may be better to follow #1 above or #3 below.

3)  More than one week: Normally we recommend that all heated zones of the GC (injection port, oven, and detector) be cooled to room temperature. All gases are then turned-off. The column should be removed, the ends plugged or capped, the column placed in an appropriate storage container (such as the original Restek box) and stored in a safe place until it is needed.

 

Here are just a few additional notes I thought worthwhile to mention:

A)  Never plug the ends of a packed column or micropacked with septa as you risk getting septum pieces inside the column; and since you should never cut (or trim) the ends of a packed column, there will not be an easy way to remove these particles. Instead, use the compression fittings and/or the column end caps which came with your packed column.

B)  For capillary columns, pieces of used injection port septa work well.

C)  Always let the GC pressure reach atmosphere before removing the column. This is especially true of packed/micropacked columns because if you don’t allow the pressure in the column to equilibrate with the outside air, the surge when the column is removed from the inlet may cause the bed to collapse and particles to be expelled.

D)  Always follow the recommendations of the manufacturer for proper detector gas flows and temperatures when the instrument is idle.

E)  If the column had been removed for storage, don’t forget to purge the reinstalled column while the GC is cool to remove all traces of air from the injection port and column before heating. During this purge, check for leaks using an electronic leak detector.

 

I hope you have found this information helpful. If you have any questions, give us a call.