PolytheneSam (Master Searcher)
02-07-02 12:35
No 266410
      preserving chemicals  Bookmark   

Here's a patent on preserving wines with a gas (CO2).  Maybe this could be applied to opened bottles of chemicals.  You could use N2 if CO2 reacts with the chemical.

http://l2.espacenet.com/dips/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US4477477&ID=US+++4477477A1+I+

http://www.geocities.com/dritte123/PSPF.html
 
 
 
 
    Osmium
(Stoni's sexual toy)
02-07-02 12:58
No 266412
      Re: preserving chemicals  Bookmark   

It's not uncommon at all to store sensitive chemicals under N2 or Ar, and some chems (metal-organics especially) have to be stored like that. Even regular food is often stored under protective gasses.

I'm not fat just horizontally disproportionate.
 
 
 
 
    PolytheneSam
(Master Searcher)
02-08-02 00:44
No 266668
      Re: preserving chemicals  Bookmark   

How about after opening?

http://www.geocities.com/dritte123/PSPF.html
 
 
 
 
    foxy2
(Distinctive Doe)
02-08-02 09:25
No 266829
      Re: preserving chemicals  Bookmark   

Yes after opening also.

Fully Informed Jury! (http://www.fija.org/)
 
 
 
 
    Osmium
(Stoni's sexual toy)
02-08-02 11:36
No 266870
      Re: preserving chemicals  Bookmark   

You cannot transfer these sensitive chemicals by pouring for obvious reasons, that's why you have to use needles, syringes, Schlenk glassware, septa and stuff like that.

Examples are grignards, BuLi, aluminum alkyls etc.

I'm not fat just horizontally disproportionate.
 
 
 
 
    foxy2
(Distinctive Doe)
02-08-02 16:59
No 266934
      Re: preserving chemicals  Bookmark   

Well I have seen 4L bottles of THF that say purge with nitrogen after opening.

These are surely transfered by pouring.
tonguetonguewink

Fully Informed Jury! (http://www.fija.org/)
 
 
 
 
    Osmium
(Stoni's sexual toy)
02-08-02 17:04
No 266936
      Re: preserving chemicals  Bookmark   

And your point is?

I'm not fat just horizontally disproportionate.
 
 
 
 
    foxy2
(Distinctive Doe)
02-08-02 17:51
No 266951
      Re: preserving chemicals  Bookmark   

That such purgeing is applicable to other chemicals besides the "super sensitive" ones you describe.

For instance anything that forms peroxides, LAH ect

And I just like contradicting you.
tonguelaugh
 
 
 
 
    Osmium
(Stoni's sexual toy)
02-08-02 18:34
No 266967
      Re: preserving chemicals  Bookmark   

Where is the contradiction?

I'm not fat just horizontally disproportionate.
 
 
 
 
    foxy2
(Distinctive Doe)
02-08-02 20:53
No 267032
      Re: preserving chemicals  Bookmark   

Did ya have to pull out the dictionary and get technical on my ass.  Your right.
blush

Fully Informed Jury! (http://www.fija.org/)
 
 
 
 
    PolytheneSam
(Master Searcher)
02-09-02 01:00
No 267166
      Re: preserving chemicals  Bookmark   

I've noticed a precipitate forms in olive oil after its been opened and left in the refrigerator.  Also, I've seen a precipitate form in a very old bottle of sassafras oil that had been opened.  Maybe oxygen in the air had something to do with it.

http://www.geocities.com/dritte123/PSPF.html
 
 
 
 
    Rhodium
(Chief Bee)
02-09-02 02:30
No 267216
      Re: preserving chemicals  Bookmark   

The olive oil thing is due to some of the oils has crystallization points above the temp in yuor fridge. No chemical transformation has occurred.
 
 
 
 
    PolytheneSam
(Master Searcher)
02-09-02 16:20
No 267419
      Re: preserving chemicals  Bookmark   


The olive oil thing is due to some of the oils has crystallization points above the temp in yuor fridge. No chemical transformation has occurred.



   
There's NO precipitate when an UNOPENED bottle is put in the refrigerator.


http://www.geocities.com/dritte123/PSPF.html
 
 
 
 
    Osmium
(Stoni's sexual toy)
02-09-02 22:02
No 267486
      Re: preserving chemicals  Bookmark   

Leave it in there for long enough and there will be precipitation too.

I'm not fat just horizontally disproportionate.
 
 
 
 
    PolytheneSam
(Master Searcher)
02-09-02 22:21
No 267490
      Re: preserving chemicals  Bookmark   

>I'm not fat just horizontally disproportionate.

Its recommended that people keep their saturated fat levels below 20 g/day.  I tried it, became even more superhuman than I was before, lost weight and decided to stay on a low saturated fat diet.  Olive oil has been found to lower the risk of heart disease.  That's why I use it.  Its high in monounsaturated fats.

>Leave it in there for long enough and there will be precipitation too.

I left an unopend bottle in the refrigerator for a couple days one time and there was no precipitation.

http://www.geocities.com/dritte123/PSPF.html
 
 
 
 
    Stonium
(Moderator)
02-10-02 17:53
No 267738
      Re: preserving chemicals  Bookmark   

Maybe a couple days wasn't long enough. tongue
 
 
 
 
    PolytheneSam
(Master Searcher)
02-10-02 21:25
No 267784
      Re: preserving chemicals  Bookmark   

Come to think of it it was in the frige for 2 weeks not a couple days. tongue



http://www.geocities.com/dritte123/PSPF.html
 
 
 
 
    Rhodium
(Chief Bee)
02-11-02 17:56
No 268094
      Re: preserving chemicals  Bookmark   

In my local grocery store they apologized for the olive oil having a white precipitate, because they had left the bottles out in the cold before they put them on the shelves, and reassured the customers that it would return to normal if stored at room temp for a few days.
 
 
 
 
    PolytheneSam
(Master Searcher)
02-12-02 01:09
No 268241
      Re: preserving chemicals  Bookmark   

That's what happens to mine when I take the opened bottles with the precipitate out of the refrigerator and let them warm up.  I'll have to get a new bottle and check to see if the brands I use do this when unopened.

http://www.geocities.com/dritte123/PSPF.html