December 15, 2019, 01:12:23 AM
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Topic: Chloroform stabilisation  (Read 206 times)

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Offline eb51111

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Chloroform stabilisation
« on: July 31, 2019, 01:21:35 PM »
I am using rotavap to remove chloroform from samples - but then re-using (to avoid wasting useful solvent - and cost of new CHCl3) the distilled chloroform for more samples - that are again rotavapped and so on etc etc.

My question, the chloroform is stabilised with around 1% ethanol (I assume to prevent COCl2) and HCl formation in air - although theoretically the ethanol (should) be rotavapped over at around the same pressure - is there any problem with using the distillate again or is it appreciably more likely to decompose and should I re-add 1% abs. EtOH to ensure stabilisation? I'm not sure the extent that chloroform undergoes this reaction and on what timescale.

Any help greatly appreciated.

Thanks.

Offline Corribus

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Re: Chloroform stabilisation
« Reply #1 on: July 31, 2019, 01:48:57 PM »
In grad school we used recycled solvents for things like column chromatography. I think as long as you're not planning on storing the recycled solvent for months, you'd be fine without adding anything to it. 1% ethanol will change the polarity of the solvent, just be aware of that.
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

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