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I need to transfer a 5 litre container of oxygen sensitive liquid chemicals within an inert atmosphere to smaller 100ml bottles. I'm going to do so using a vacuum glove box purged with nitrogen. I have very little experience using a glove box but as far as I understand, you'd first pull a vacuum for the main chamber a few times to remove any oxygen, moisture and contaminants, then purge it with nitrogen. Afterwards place the item you wish to bring into the glove box inside the antechamber, pull a vacuum within the antechamber a few times like before then purge with nitrogen to meet the same kind of atmosphere as the main chamber, then open the antechamber latch within the main chamber to bring in your item. Proceed with the operation.

The obvious issue here is a vacuum would boil the liquid chemicals if not effectively sealed. But the whole point of this operation is to only open the 5 litre container once inside an inert atmosphere, but I can't bring it into that atmosphere without risking the safety hazard of placing it under a vacuum prior to purging. The only idea I have is to simply not run a vacuum for the antechamber and just purge it with nitrogen, but of course would defeat the purpose of working in an effective inert atmosphere. The state of the unopened container is sealed with a standard commercial heat induction sealed liner like you'd find for unopened liquid medicines, and with a child safe cap.

Any recommendations to how I can ship this safely into the glove box?

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  • $\begingroup$ One would hope the bottle is effectively sealed or your chemical is toast already… $\endgroup$
    – Jon Custer
    Sep 30, 2021 at 14:07
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    $\begingroup$ Why do you want to do that in a glove box? I give you 10:1 this a bad, bad idea. Use your Schlenk line. Especially if you have little experience with glove boxes: don't use them if at all avoidable. $\endgroup$
    – Karl
    Sep 30, 2021 at 14:17
  • $\begingroup$ The same concern expressed by Karl is valid for a Schlenk line, if the operator has no idea of it. Another point: normal glove box don't require vacuum cycle, they are leaking, etc. The vacuum is necessary to purge the antechamber. I think you should give us more details. Nature and purpose of the liquid. It is possible that you can do that in open air or that you simply insert the big one. Actually the atmospheric P does nothing to liquid inside (otherwise it won't be sealed). $\endgroup$
    – Alchimista
    Oct 1, 2021 at 9:53
  • $\begingroup$ No normal bottle that is sufficient to contain an air sensitive chemical will explode under vacuum. An the lid should be sufficient to hold the content it too. Also, most such bottles are designed to make it easy to get the content out while retaining protection from air (eg by having a rubber seal which can allow transfer of a measured amount by syringe). Take advice from experienced chemists who use these techniques routinely. $\endgroup$
    – matt_black
    Oct 1, 2021 at 11:15

1 Answer 1

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  • Check if there is no better way (e.g., cannulation on a Schlenk line), especially if the solvent of your solution is flammable. If you know the density of the solution (even an approximate value), you may infer the volume transferred by monitoring the mass of the smaller flasks empty vs. flask filled.

    As an example, the steal barrels of predried solvents on a solvent system (like this) are equally put on a (e.g., bathroom) balance to check how much these still contain.

  • If it still has to be the glovebox, check with the responsible for the glovebox if the bottle still is small enough to be carried safely on the lock's table. Equally consider the weight of such a flask, the table might not slide as easy as for a small $\pu{100 mL}$ flask on the tray. If the flask is stuck or (beware) tipping, the constraint access of the lock from inside of the chamber may be a source of trouble.

    If possible, let him/her transfer the bottle for you (especially at this scale). Check if the containers (both the one for $\pu{5 L}$ as well as the subsequently to be used to $\pu{100 mL}$ each) are in good mechanical condition. Be fine if he/she refuses this operation.

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  • $\begingroup$ I can't make head or tail of the first and last paragraph in the text you quote. And the procedure in the second will not dry a liquid. Probably OK for chemistry that requires very modest inert conditions, but why use a glove box in the first place then? $\endgroup$
    – Karl
    Sep 30, 2021 at 16:03
  • $\begingroup$ That procedure in the third paragraph is hillarious. It will reduce the oxygen content in the antechamber by 45%. $\endgroup$
    – Karl
    Sep 30, 2021 at 16:18
  • $\begingroup$ Re first paragraph: Transfer of a clean, small pristine bottle (say $\pu{100 mL}$ dry toluene), septum never pierced, may be acceptable. The turn of the screw cap mainly is mechanical convenience; it helps a bit to access the septum if the screw cap was turned a little (to break its connection with the lower ring) when the bottle still was outside the box compared to doing all with the bottle in the box across the gauntlets and gloves. But this brief turn is just before adding the flask to the tray and closing the lock. $\endgroup$
    – Buttonwood
    Sep 30, 2021 at 20:20
  • $\begingroup$ Paragraph two and three are more about «bring your own round bottom flask to the glovebox» which may be okayish; apparently (aka group policy), there are groups who permit these with liquids already inside the round bottom flask. (The purge with nitrogen ahead of the transfer into the box reminds a bit to degassing solvents for the HPLC in the ultrasound bath; with no drying effect [i.e., it may rather saturate the solvent with water vapour]). Overall (anticipated scale, demand of dexterity/equipment/time, ease of accessing the bottles), cannulation on a Schlenk line were my preference here. $\endgroup$
    – Buttonwood
    Sep 30, 2021 at 20:35
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    $\begingroup$ @Karl Given the oil pump on the floor, it will be easy to mistake $\pu{-15 mmHg}$ relative pressure (against atmospheric pressure) with $\pu{15 mmHg}$ (and well less) absolute pressure, too. This and your argument are convinced me for an edit. $\endgroup$
    – Buttonwood
    Oct 6, 2021 at 6:39

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