[Nhcoll-l] off-coloured EtOH

[Simon Moore]

If the ethanol was diluted with tap as opposed to deionised water, to 70% then the alcohol will cause a light precipitate from the water and the alcohol does go a faint yellowish colour - in my experience!
Otherwise I have not (yet!) experienced the problem and I purchase my alcohol in poly-propylene containers.

With all good wishes, Simon.

Simon Moore MIScT, RSci, FLS, ACR
Conservator of Natural Sciences and Cutlery Historian, 



www.natural-history-conservation.com 




> On 20 Mar 2020, at 14:28, Callomon,Paul <prc44 at drexel.edu> wrote:
> 
> If you are diluting 95% ethanol that came in plastic drums from a reputable supplier like Pharmco, then in the absence of specimens the only thing that can cause discoloration is something in your water. That's more chemistry than I learned in school, but my guess would be metals (iron, perhaps, or copper). 
> If the ethanol was clear before dilution, then unless it was somehow contaminated to start with it's not going to be the source of the issue. 
> "When you eliminate the impossible, whatever remains - however improbable - must be the truth" (attrib. S. Holmes)
> 
> 
> Paul Callomon
> Collection Manager, Malacology and General Invertebrates
> Academy of Natural Sciences of Drexel University, Philadelphia
> callomon at ansp.org Tel 215-405-5096 - Fax 215-299-1170
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