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The_Davster
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Neutrino, where were you able to get teflon sheet?
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neutrino
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I got thin (~1mm) sheet as part of an eBay auction. Look there for Teflon or PTFE.
edit: Yay, 1000th post
[Edited on 12-9-2005 by neutrino]
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garage chemist
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It's starting to get really cold outside (already below zero in the night, and hardly above 5°C during daytime), and my chems are in my garage
which is noninsulated and not heated.
My glacial acetic acid froze long ago (as you would expect... but it is very prone to supercooling) and today I looked after my benzene (analytical
grade, very pure) and it was completely solid too.
However, I warmed the bottle and the frozen benzene did not swim on the liquid, but rather was on the bottom!
This proves that solid benzene has a higher density than liquid benzene, and that benzene contracts during freezing instead of expanding.
This further proves that there is no danger of a glass bottle with benzene rupturing when freezing.
Same goes for glacial acetic acid- frozen acetic acid sinks in liquid acetic acid.
The well- known destructive force of freezing water is reserved to water itself. It is an anomaly that only water possesses. Most other chems increase
their density when freezing, posing no danger.
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12AX7
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| Quote: | | Originally posted by garage chemistThe well- known destructive force of freezing water is reserved to water itself. |
And bismuth. (And a number of other curious chemicals.)
Tim
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garage chemist
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Yes, you're right about bismuth. But that is no problem, of course, unless you normally store it molten.
But now I remember something curious I noticed during an experiment- molten anhydrous potassium acetate, when solidifying, forms a crystal crust which
always gets a hole in it where liquid material oozes out! It looked really strange and that's why I remember it. Maybe CH3COOK also has this
anomaly.
[Edited on 20-11-2005 by garage chemist]
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Zinc
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I store all my chemicals in my home lab in their original packages.
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Jdurg
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BTW, just thought I'd point out that even if it is sealed in a glass ampoule, halogens will leach through it somewhat. I noticed today that the box I
store my F2, Cl2, Br2 and I2 in had a funky bleach-like odor to it when I opened up the lid. While there is no noticeable breach on any part of the
glass, when you put your nose near the glass you can smell some halogen coming out. So keep that in mind when you think about where to store your
halogens.
\"A real fart is beefy, has a density greater than or equal to the air surrounding it, consists of the unmistakable scent of broccoli, and usually
requires wiping afterwards.\"
http://maddox.xmission.com. |
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woelen
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Hmmm, this does not sound good. How thick is that glass from these containers? I have two 30 year old glass ampoules with bromine (each one contains
250 ml of reagent grade bromine). I do not have the idea that any bromine leached out, the glass also still looks perfectly clear, but I'll stick my
nose in the containers, in which I store these, to see whether there is smell or not.
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neutrino
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What kind of glass? I could see liquid bromine eating its way out of soda-lime over a very long time period.
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Jdurg
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These are standard, borosilicate glass test tubes that have been melted shut on one end to seal in the halogen. It's frustrating because I figured
that they would be able to hold in the halogen without any issues. I will admit, however, that the amount of halogen leaking out isn't all that great
since I have a lot of stuff in the same area that aren't showing one bit of corrosion. (I keep an ingot of .999 pure silver in the box as a way to
tell if there is major leaking going on). It is definitely noticeable and I cannot tell if it is the iodine or the bromine that is leaking. It
doesn't have that skunk smell like Br2 has so I'm leaning more towards the iodine.
The iodine had melted into a liquid while the sealing process was going on, so I don't know if the liquid I2 had slowly worked its way into the glass
and is now very slowly leaching away. The human nose is VERY good at smelling halogens in low concentrations, so I'm not mortified that I can smell
it. I'm just a bit shocked and hoping that it's not a sign of a sudden failure in an ampoule. 
\"A real fart is beefy, has a density greater than or equal to the air surrounding it, consists of the unmistakable scent of broccoli, and usually
requires wiping afterwards.\"
http://maddox.xmission.com. |
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Fleaker
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"BTW, just thought I'd point out that even if it is sealed in a glass ampoule, halogens will leach through it somewhat. I noticed today that the box I
store my F2, Cl2, Br2 and I2 in had a funky bleach-like odor to it when I opened up the lid. While there is no noticeable breach on any part of the
glass, when you put your nose near the glass you can smell some halogen coming out. So keep that in mind when you think about where to store your
halogens. "
Perhaps it's the fluorine gas eating through the glass? On Theodore Gray's website, there is a picture of fluorine gas ampouled. It's my
understanding that if the fluorine is not absolutely anhydrous, it will corrode glass easily.
Here is that link: http://theodoregray.com/PeriodicTable/Elements/009/index.s7....
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The_Davster
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Someone here posted something about heating a glass tube which had once been used to distill bromine, and bromine that was trapped in the glass was
given off. If bromine can be trapped in glass for years, is it so unrealistic that it could go all the way through an ampoule?
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Jdurg
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| Quote: | Originally posted by rogue chemist
Someone here posted something about heating a glass tube which had once been used to distill bromine, and bromine that was trapped in the glass was
given off. If bromine can be trapped in glass for years, is it so unrealistic that it could go all the way through an ampoule?
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I think that was actually me who had mentioned that.  Upon a more thorough
inspection, I have determined that it is indeed the bromine which is slowly seeping through the glass. I have been able to identify a slight odor
coming out from where the glass ampoule was sealed. I plan on covering that area in some type of sealant to see if that will retard the odors. It's
not anything really bad that has me completely worried. The metals that are in the area aren't corroded at all. It's just that when I can smell the
halogens after figuring that I had them sealed away for ever it kind of pissed me off.
\"A real fart is beefy, has a density greater than or equal to the air surrounding it, consists of the unmistakable scent of broccoli, and usually
requires wiping afterwards.\"
http://maddox.xmission.com. |
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neutrino
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It sounds to me like you might have a small hole in that seal.
For those who have never tried it, sealing bromine in a glass ampoule is rather tricky. Unless you leave a lot of space between the seal and the
bromine and work very quickly, you will heat the bromine up a little. If it is already at room temperature, this small temperature increase will
increase its vapor pressure by a good fraction of an atmosphere.
If the glass gets hot enough for a proper seal, it will seal but then the expanding vapor will cause the molten glass to pop. A very big bubble with a
small (but probably still visible) hole will remain.
But if the glass doesn’t get hot and fluid enough, a small but steady stream of bromine vapor will flow through the hole you’re trying to close
and (combined with the high viscosity of the glass) prevent the seal from closing properly. In the times I have tried it it always left a visible
hole, but your case may be different.
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The_Davster
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I was actually thinking of trying this in the lab I work at, I have keys, so I can go in late and have fun...I mean...get ahead in my research... But I was thinking of using LN2 to freeze the bromine in the glass tube, then seal
it. Would the pressure increase after it melts be too great for the quartz glass tube to take? We use an oxy-hydrogen torch, so it takes very little
time to melt the quartz glass tubes.
[Edited on 20-7-2006 by rogue chemist]
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neutrino
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As long as it stays cool and its vapor pressure can't increase dramatically, you won't have a problem. Just make sure the bromine stays cool (frozen
if possible), work fast, and get the quartz fluid enough for a proper seal.
You probably already know this, but eye protection is a must with quartz. By the time it's fluid it's putting out a very high flux of visible and IR
radiation. If you have a brazing mask, wear it.
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YT2095
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Hey JDurg 
another idea for you to consider (It`s one I use myself) is if you have glass tubing, the sort I have is 50cms lond and 6mm ID. I melt the one end
letting the fluidity and Gravity do all the work for me until I`m satisfied with the seal after cooling.
I Then cut the excess tube off leaving my vial with a good 40mm extra than I need.
Introduce your element (fill with inert gas where applicable), and then heat the area outside the vial at the 40mm extra mark, as it softens a GENTLE
twisting action (if you feel resistance your putting on too much pressure! you`ll create your seal.
heat a little upwards now towards the excess in the 40mm, and again gently pull the glass appart, similar making a pipette/eyedropper, when that`s
gone out the way heat the peak left on your vial, again letting gravity do the work until it forms a nice thick dome.
allow to cool
obviously with bromine the same thing applies but you`ll need some sort of Ice/freezing pack around your bromine level and a little above to keep it
at least Liquid.
it works for me anyway, Good Luck
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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Jdurg
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I'm certain that there is no hole as for the first 1.5 to 2 years there was absolutely NO odor at all. It's only recently that I noticed the faintest
of faint smells. When it's kept inside the storage box nothing escapes odor wise so I'm not completely worried about it. It's more of a "damn it"
type of thing than an "OH SHIT!!!!!!" 
\"A real fart is beefy, has a density greater than or equal to the air surrounding it, consists of the unmistakable scent of broccoli, and usually
requires wiping afterwards.\"
http://maddox.xmission.com. |
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froot
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I have been pondering this very issue for a while now. As my chemical collection grows, so does the potential danger.
At the moment I have my chems in my garage which is downstairs under the house. They are in an old steel kitchen cupboard and everything is together.
Now there is a huge red light flashing in my mind.
Proper storage of chemicals in a residential area is never that important until something goes wrong and hindsight is a pain in the ass.
I am planning to make a well ventilated outside shed detached from the house out of an inert substance such as asbestos sheeting, yes we still get
that here. I'm thinking of a worst case scenario where 2 incompatable chems come in contact with each other and ignite, setting the rest of the store
alight along with the other chems. That is a real sobering thought and can very easily happen.
As far as storing chems together, does this sound correct?.....
Primary acids together,
seperated from
Primary bases together,
seperated from
Organics together (including solvents),
seperated from
Inorganics and metals together
Please advise if necessary...
Oh and one more thing...a fire extinguisher is like a parachute, a godsend when you need one. What type would you recommend?
[Edited on 24-7-2006 by froot]
We salute the improvement of the human genome by honoring those who remove themselves from it.
Of necessity, this honor is generally bestowed posthumously. - www.darwinawards.com |
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YT2095
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that`s not a bad way to do it either
I tend to go for a more simplified version, and keep Oxidisers away from Reducers.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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woelen
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Jdurg, a very easy and safe way to absolutely have no bromine around is to store the ampoule of bromine (and also of iodine, chlorine) in a box, in
which also some sodium thiosulphate is stored (so-called hypo). Sodium thiosulphate is air-stable and non-hygroscopic, but it reacts quickly with even
the tiniest traces of free halogen.
I have taken a film-canister for 24x36 mm standard photo-film, put this half full of solid crystalline Na2S2O3.5H2O (fairly large crystals, well over
1 mm diameter) and made hundreds of small holes in the canister with a thin needle. This canister I store in a simple tupperware-like plastic box,
together with my halogens. It works very good. No smell of halogens at all. Any halogen, which is released, will be absorbed by the hypo. In your case
with the sealed ampoules, you will never have to replace that canister, it will last for many many years.
In fact, the large 250 ml ampoules of bromine, I had, were shipped in big plastic jugs, together with 1 kg of sodium thiosulfate in a special woven
bag, which allows air/gases to pass, while the crystals stay inside. In case of an accident, where lots of bromine gas could be released, it quickly
is absorbed by that hypo.
Froot, I would, as YT2095 mentioned, also keep oxidizers and reductors separate. Then you have the following compartments:
- Acids
- Bases
- Organics, liquid
- Oxidizers
- Reductors
- Generic solids
The reductors and generic solids can fairly safely be combined. That is what I do. I also separately store my 30% H2O2, as a lone bottle, away from
anything else.
I also use stock storage and usage storage. From my chemicals, I always take a small portion, put that in a photo roll canister, and I store the
original container separately, sometimes with plastic bags around them, or the container stored in a larger separate container. That latter thing I do
is to prevent fresh air going in and out all the time the temperature changes. Especially carefully closed plastic bags around the container have
proven very useful. They shrink and expand with changing temperatures, but the air in them is only very slowly replaced. In this way, I have been able
to keep a sensitive chemical like Na2S very good for many years, while Na2S from the same original container, but stored in a normal container, now is
covered with a thick oxidized layer of Na2SO3/Na2SO4/Na2S2O3.
Of course, I only do this extensive packaging for my stock storage. The working canisters are placed, such that they can easily be grasped and opened.
[Edited on 24-7-06 by woelen]
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The_Davster
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The chemicals in my lab are organized as such:
Acids
Bases
oxidizers
general inorganic
organic
metals are in a completly different cabinet, you know, keep them shiny.
Outside: Big solvent cans, assorted nasties(phenol, WCl6)
Potentially very dangerous acids, like my perchloric, is in a margaine tub should it ever leak, and to keep its 'acid ring' separate from other acid
rings.
I dispense acids into smaller ground glass bottles to avoid handling the big jugs all the time.
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froot
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I keep my U235 in the fridge, keeps the food fresh for ages
Thanks for the input, arrangement of storage modified...
I like the idea of placing the bulk storage bottles in plastic bags, makes good sense. I'm actually too embarassed to tell you whats currently sitting
together in the same cupboard, which will be remedied as soon as I get home this afternoon.
We salute the improvement of the human genome by honoring those who remove themselves from it.
Of necessity, this honor is generally bestowed posthumously. - www.darwinawards.com |
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YT2095
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just out of pure curiosity here, might there be some sort of backhanded Logic in storing acids AND bases together?
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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neutrino
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Imagine if a large container of sulfuric acid burst and started attacking a container of a strong base. If it got through, the resulting reaction
would release large amounts of energy, producing lots of heat, gas, foaming acid, etc. It would be somewhat neutralized at the end of all this, but
the energy released would cause a lot of damage.
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