Sciencemadness Discussion Board

after packing chromatography column

soma - 13-1-2017 at 01:22

Would there be a problem if after packing the column (for gravity or flash) it is left for many hours before using it? (Keeping a layer of solvent above the silica).

(I had posted this in another thread with a different subject but thought it would to better to have its own subject.)

[Edited on 13-1-2017 by soma]

Tsjerk - 13-1-2017 at 01:37

Should be no problem as long as you don't have a gradient in the column.

Metacelsus - 13-1-2017 at 05:55

It's fine.

phlogiston - 13-1-2017 at 17:48

As Metacelcus and Tsjerk already said: thats perfectly fine. You can store it like that indefinitely. However, do avoid significant temperature fluctuations. That could cause dissolved gasses to 'precipitate' (I suspect that's not the proper word for a gas, suggestions?) forming bubbles that will ruin your nice packing.

[Edited on 14-1-2017 by phlogiston]

CharlieA - 13-1-2017 at 17:57

effervesce

PHILOU Zrealone - 14-1-2017 at 11:20

Quote: Originally posted by phlogiston  
That could cause dissolved gasses to 'precipitate' (I suspect that's not the proper word for a gas, suggestions?) forming bubbles that will ruin your nice packing.

[Edited on 14-1-2017 by phlogiston]

"Degas/degassing", "bubbles/bubbling", "boils/boiling" and "bubble coalescence" are what you are after I think ;)

CharlieA - 14-1-2017 at 18:07

The release of dissolved gases (the subject under discussion) is not the same as "boils/boiling." "Degas/degasing" and effervescence are relevant terms to describe the release of gases from a solution.

phlogiston - 15-1-2017 at 15:18

Thanks guys, looks like 'to effervesce' is indeed the verb I was looking for. Added another useful word to my vocabulary.

JJay - 15-1-2017 at 18:26

How much material can be reasonably separated in a 50 mL burette? I realize that there's probably no one answer for this, but is there a rule of thumb I could use?

I'd hate to waste any material that I considered valuable enough to chromatograph....