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Sandbag
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"dry" acetone
What exactly is this "dry" acetone, and how might one go about converting normal liquid acetone to "dry" acetone?
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ADP
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Well generally, dry means without water, so I would assume well actually I know it means anhydrous acetone. A small amount of water is in OTC acetone
thats why its referred to as dry.
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Sandbag
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So lab grade acetone would be as "dry" as it comes, correct? And anhydrous normally refers to a gaseous state, we're still talking
about a liquid, right? Just liquid tone with little to no dilution in water.
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Kinetic
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Acetone
| Quote: | | And anhydrous normally refers to a gaseous state |
I think you had better check up on that statement.
Lab grade acetone would not be 'anhydrous'. Howerver, it would not contain much water and is suitable for most uses as is. Futher drying
must be done using a drying agent of some sort - for example, distilling your acetone from anhydrous calcium chloride. Acetone is a bit tricky since
it can react with common drying agents such as CaH2, and probably also with Na and P2O5.
If you insist on the gaseous option, you can get really dry acetone by heating it in an open container to 100 degrees C or so.
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Organikum
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After my understanding "dry" may include traces of water as they come in by the usual humidity of the air, "anhydrous" is
completely without any water.
Gaseous or liquid has nothing to do with it.
I wouldn´t use CaCl2 for drying acetone, the drying agent of choice is sodium carbonate.
Keep in mind that all drying of liquids takes time and stirring speeds the process up.
And yes: I would regard a fresh bottle bottle of labgrade acetone as "dry".
/ORG
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kazaa81
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I'm having troubles getting acetone at hardware stores....they want to sell me what they call "acetone" even if it isn't wrote on
the can containing it (some toluene and other dirt...)
Has anyone get success buying it in non-USA. Please consider i'm in holiday in Italy.
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FrankRizzo
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If you're drying the acetone for use in pyro, calcium chloride (Damp-Rid) works just fine. Funnel in ~1/2 cup per quart and wait a day or two
before using it.
For syths or other uses, use 3A molecular sieves. Just pour a bunch into the can, and the sieves will soak up the water and a bit of acetone.
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unionised
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" the drying agent of choice is sodium carbonate"
Sounds like a synthesis of diacetone alcohol to me.
CaCl2 works well enough and, if you are fussy, distilling it will clean it up ver well.
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mick
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I have read that molecular sieve can cause self condensation of acetone which would produce water. I would not have thought it was very fast so drying
overnight, decanting and distilling could give dry acetone but storing over molecular sieve might be a problem.
If you are doing water sensitive reactions carrying out a small scale reaction with dryish solvent first and distilling out the solvent before
quenching etc might give you good quality solvent for the main reaction. A lot of variables though.
If you distil ethers and store them be careful, peroxides can form quite fast without the stabilizer even in a brown bottle.
mick
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neutrino
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Acetone is a ketone, not an ether.
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new_chemist302
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Acetone can be dried by adding oven baked Epsom Salt to it, then filtering, or just leave the MgSO4 in the bottom of the acetone and decant off what
you need.
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turd
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From "Purification of Laboratory Chemicals":
It can be dried with anhydrous CaSO4, K2CO3 or type 4A Linde molecular sieves, and then distd. Silica gel and alumina, or mildly
acidic or basic dessicants cause acetone to undergo the aldol condensation, so that its water content is increased by passage through these reagents.
This also occurs to some extent when P2O5 or sodium Amalgam is used. Anhydrous MgSO4 is an inefficient drying agent, and CaCl2 forms
an addition compound. Drierite (anhydrous CaSO4) offers he minimum acid and base catalysis of aldol formation and is the recommended drying agent for
this solvent.
(\em added)
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FriendlyFinger
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Then it says shake for a few hours with 25g/l CaSO4, decant and distill through a column with 10g/l CaSO4. Is Sodium Carbonate better?
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FriendlyFinger
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7) What's the story with molecular sieves and acetone?
"Purification of laboratory chemicals" 5th edition page 29 says;
"However, care must be exercised in using molecular sieves for drying organic liquids. Appreciable amounts of impurites were formed when samples of
acetone, 1,1,1-trichloroethane and methyl-t-butyl were dried in the liquid phase by contact with molecular sieves 4A (Connett lab pract 21 545 1972)"
The book also sugests that MgSO4 is acidic enough to cause some adol condensation
In 3l of hardware acetone, I put a couple of spoon full of anhydrous MgSO4, that was boring so filtered that off after only 15 min, then put in 500g
of freshly activated 3A molecular sieve beads and left over night.
Next day, poured into a flask and distilled. Started out at 56 deg and after about 2l had come over, temp was at 56.5 deg then with about 500 ml left,
temp started shooting up to 60 deg, so I stopped.
Some of that acetone was used to gas some benign freebase and left the salt with an increadibly foul smell. 125ml of this acetone was vacuum
distilled, bath at 25 deg wich left about 5ml of an oily substance with the same foul smell and it wasn't freebase because yield of salt was 94%.
After acetone was gone from the molecular sieves, they were put in the oven and the same foul smell started eminating. So I've probably got some
diacetone alcohol and who knows what else.
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turd
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| Quote: | | "However, care must be exercised in using molecular sieves for drying organic liquids. Appreciable amounts of impurites were formed when samples of
acetone, 1,1,1-trichloroethane and methyl-t-butyl were dried in the liquid phase by contact with molecular sieves 4A (Connett lab pract 21 545 1972)"
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I stored dry acetone over mol sieves for 2 weeks and couldn't detect any condensation products neither by GC/MS nor by 1H-NMR. I wouldn't store it for
longer than that though.
| Quote: | | Some of that acetone was used to gas some benign freebase and left the salt with an increadibly foul smell. |
Why would you bubble a strong acid through acetone? Containing an amine of all things?
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Organikum
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After drying acetone with sodium carbonate I never detected any condensation products, but I admit that I simply not looked so much either. I buy my
hardwarestore acetone which is some 98,8% min. trusting the datasheet, dry it with the carbonate, filter an distill. For serious synthesis I use only
the middle run of the distilation, say some 80%. Was always perfect for me. The rest I use for cleaning purposes.
Anything wrong with this?
??
/ORG
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cbfull
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This is an interesting thread. I have read from some sources that acetone is tricky to dry, and another source stated that phosphorous pentoxide
(P2O5, as stated earlier) should be used and then the acetone is distilled off. I don't think I would trust the P2O5, because the hydrolysis product
is phosphoric acid.
It sounds like drierite is your safest bet, which has been freshly dried following the instructions for drying drierite exactly. Apparently, Drierite
needs to be re-dried in a very specific way (temperature, time, etc.) for it to do a really good job.
Lab grade acetone is typically <0.5% water, which is not really too bad. I don't know exactly how dry it needs to be for whatever application, but
there's my 2 cents.
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battery
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can any1 here give me any good recipies for good explosives and can you send me a list of chemicals used in home made explsovies eg.acetone and what
they come under in shops and were to get them from talk on here or email me please
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DrP
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Excuse my ignorance, but what does KEWL mean? Does it mean fucking dick head who is likely to blow himself up?
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enhzflep
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| Quote: | Originally Posted by DrP,
but what does KEWL mean? Does it mean fucking dick head who is likely to blow himself up? |
Yeah, that's pretty much what I've always taken it to mean. Although, in a greater context it may taken to mean somebody who is exagerating and more
likely to discuss items/topics designed to elicit the response "Cool!" This person most commonly knows very little on the topic of which they speak -
though in the vast majority of cases they believe (and occasionally do) that they know vastly more than those subject to said speech.
This type of personality combined with what are usually gaping holes in knowledge is a deadly mix once added to this hobby.
Take for example the 15yr old boy from Sweden that blew himself up a number of years ago. He was all over RS.org talking about how he had all this AP
and would mix it with some AN he had 'to make one big effen bomb'
A number of members told him to be carefull, and that that much AP was suicidal, but he disregarded them - too keen to take advantage of the fact he
could impress his mates whilst mummy was away for the weekend.
Turns out that one night after posting, he did do himself a mischief - with 800gms AP no-less!!! A big mischief - DEAD.
He was waaaaay kewl.
Asking for freely available recipes, with no apparent effort to discern those that are bullshit from those that are genuine is quite definitely
another manifestation. Is that what you were getting at DrP? 
[Edited on 29-6-2006 by enhzflep]
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neutrino
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The standardized definition of 'kewl' comes from the KGB files at RS. It's to long to post here, so follow the link and take a look if you're curious.
Now let's leave the old 'what is a kewl' discussion to the appropriate thread, and go back to our regularly scheduled thread about drying acetone...
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cbfull
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Can anyone tell me what kind of stuff would need acetone to be dry?
We have HPLC grade acetone at work which is <0.5% water, and if it has too much water in it then it won't dissolve the resins.
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DrP
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When I was doing my PhD, we distilled ALL solvents that were used in reactions - this eliminates ALL possibilites and arguments over wether or not
trace amounts of water have effected your results. It's up to you, but my take on it would be - if in any doubt at all then distill it and be done
with it - then you are sure and confident that you have dry product. Heck - stick one of the above mentioned drying aids in the bottom of the
distillation flask as well to make sure. EZ (E-Z - get it? Kewl eh? )
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Organikum
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Thats what Vogel writes about drying acetone and MEK:
| Quote: | The ketone is salted out from the distillate
with potassium carbonate, separated, dried with anhydrous potassium
carbonate (this will also remove traces of sulphur dioxide and carbon
dioxide present), and, after filtration, allowed to stand for several hours
over anhydrous calcium sulphate. |
Vogel rulez!
/ORG
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texas_holdem
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additional routes taken from vogels practical organic chemistry,5th edt
-------------------------------------------------------------------------
KETONES
21.ACETONE
although major impurities in the commercial grades of actone are methanol,
acetic acid and water, the analytical reagent generally contains less than 0.1 per
cent of organic impurities although the water content may be as high as 1 per cent.
Commerciall acetone may be purified in several ways:
(a) The acetone is heated under reflux with successive quantities of potassium
permanganate until the violet colour persists. It is then dried with
anhydrous potassium carbonate or anhydrous calcium sulphate,*) filtered
from the desiccant and fractionated;precautions are taken to exclude
moisture.
(b) To 700mL of actone,b.p.56-57°C, contained in a litre bottle, a solution of
3g of silver nitrate in 20mL of water is added, followed by 20mL of 1M
sodium hydroxide solution, and the mixture is shaken for about 10 minutes.
The mixture is then filtered, dried with anhydrous calcium sulphate and
distilled.
(c) When only a relatively small quantity of oure, dry acetone is required, it
may be purified through the bisulphite complex: the latter is decomposed
with sodium carbonate solution (for details, see under 22.Ethyl methyl
ketone), dried over anhydrous calcium sulphate and distilled. A more
convenient procedure is to make use of the addition compound with sodium
iodide (NaI,3 C3H6O), which decomposes on gentle heating and is particularly
well adapted for the preparation of pure acetone. One hundred
grams of finely powdered sodium iodide are dissolved under reflux in 440g
of boiling commercial acetone, and the solution is cooledin a mixture of ice
and salt (-8°C). The crystals are filtered off and quickly transferred to a
dry distilling flask, connected to an efficient condenser and to a receiver
cooled in ive. Upon gentle warming, the acetone distills rapidly.
Acetone purified by these means, or the analytical reagent grade, may have
the water content reduced by storage over a Type 4A molecular sieve. Silica
or alumina should not be used as an aldol type reaction is initiated with the
formation of water as a by-product. Pure acetone has b.p. 56.2°C/760mmHg
and is highly flammable.
*) Anyhydrous calcium chloride should not be used as some chemical combination occurs
22.ETHYL METHYL KETONE (Butan-2-one)
This excellent solvent has properties similar to those of acetone but it has a
somewhat higher boiling point and is therefore less flammable. A preliminary
purification is effected by drying the commercial product with anhydrous
potassium cabonate or anhydrous calcium sulphate, filtering from the desiccant,
and fractionating through an efficient column; the fraction,b.p.79-80°C, is
collected seperately, and is quite satisfactory for recrystallisations, This may be
futher purified either through the bisulphite addition compound or through the
sodium iodide addition compound. The ethyl methyl ketone, b.p.79-80°C,is
shaken with excess of saturated sodium bisulphite solution until reaction ceases,
cooled to 0°C, the bisulphite complex filtered off, the filter cake well drained,
washed with a little ether, and then dried in the air. The dry bisulphite complex
is decomposed with a slight excess of sodium carbonate solution and distilled in
steam. The ketone is salted out from the distillate with potassium carbonate,
separated, dried with anhydrous potassium carbonate (this will also remove
traces of sulphur dioxide and carbon dioxide present and, after filtration,
allowed to stand for several hours over anhydrous calcium sulphate. It is then
distilled. In the sodium iodide method, the ketone is saturated with sodium
iodide by boiling under reflux, the solution is filtered through a hot-water funnel,
cooled in a freezing mixture and white crystals (which have a m.p. of 73-74°C)
filtered off. Gentle heating of the crystals in a fractional distillation assembly
gives pure ethyl methyl ketone of b.p. 79.5°C/760mmHg.
-------------------------------------------------------------------------
there u go.
this has just been typed off the 5th edt.
it is almost the same text as in the 3rd, only the introduction slightly differs.
im wondering whats the contaminant in hardwarestore-tone.
im asking as i remember someone posting he had some oily
yellow substance left in the flask when distilling his.
anyone distilling their 'tone?
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