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gardenvariety
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Since you mentioned the FDA, I'll assume you're in the States. A good OTC supply of ethyl acetate is nail polish remover, at about 70ish%
concentration. One distill gets you the acetate/ethanol/water azeotrope, perhaps you can dry it and break the azeotrope from there.
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chemrox
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@rrkss-"This is counterproductive as you loose product unnecessarily washing it with water. I only do a wash with bicarbonate because my reagent in
excess was Acetic Acid."
I would anticipate a lot of foaming doing this. With a simple esterification reaction like this, involving alcohol and acid, I wouldn't wash at all.
I'd run the distillation with a frax column as mentioned several times. Reflux for 30 mins should be plenty. Acetic just isn't a strong enough acid
to catalyze the reax. Hence the SA. This could also be base catalyzed. I wonder how NaOH would work? Or a tiny bit of CaH? With NaOH you'd have
Na-acetate in solution and also some Na-ethoxide in eq. with NaOH/Ethanol. I think they all would work. Why don't you try them all and report back
with comparative yields? That would be a good beginning experiment.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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rrkss
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Quote: Originally posted by chemrox  | @rrkss-"This is counterproductive as you loose product unnecessarily washing it with water. I only do a wash with bicarbonate because my reagent in
excess was Acetic Acid."
I would anticipate a lot of foaming doing this. With a simple esterification reaction like this, involving alcohol and acid, I wouldn't wash at all.
I'd run the distillation with a frax column as mentioned several times. Reflux for 30 mins should be plenty. Acetic just isn't a strong enough acid
to catalyze the reax. Hence the SA. This could also be base catalyzed. I wonder how NaOH would work? Or a tiny bit of CaH? With NaOH you'd have
Na-acetate in solution and also some Na-ethoxide in eq. with NaOH/Ethanol. I think they all would work. Why don't you try them all and report back
with comparative yields? That would be a good beginning experiment. |
The bicarbonate wash is because a little acetic acid comes over when you stop the fractional distillation at the temperature drop (though the second
fraction is mostly water). Not much foaming at all. A second CaCl2 wash is also needed if you don't own type 4A molecular sieves to remove unreacted
ethanol.
Base catalyzed reaction would work but I prefer acid since etched glass and frozen joints aren't my idea of a fun time.
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smaerd
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Well I finally got around to doing this. As many months have passed haha.
I did a simple distillation of nail polish remover. The distillate came over at about 71*C, so I am assuming there is an azeotrope with water? That or
my thermometer is wrong(just kidding)  .
I prepped 10 grams of CaCl2 which is precipitating right now. I was assuming the azeotrope was with ethanol while it was distilling, which is why I
whipped some up really quick.
Would a fractional distillation clean this azeotrope up and get it boiling clean at ~77*C? If not I'm assuming it will still suffice for the purposes
I am using it for. Thanks for any advice.
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bbartlog
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| Quote: | | Would a fractional distillation clean this azeotrope up |
No, you can't break an azeotrope with fractional distillation.
Ethyl acetate forms azeotropes with both water and ethanol.
I think rrkss' suggestion (CaCl2 to remove ethanol and water) sounds good.
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smaerd
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Excellent thanks bbartlog! Good thing I've got some ready  .
Seriously recommend the nail polish remover distillation over ordering GAA and esterification. (edit: thought I had a 50ml receiving rbf, it was
actually 100ml hehe)It's around 60-70% concentration EA and is VERY affordable. The remaining goo left on the flask is simply cleaned with 4-5 mls of
acetone.
[Edited on 16-1-2011 by smaerd]
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The WiZard is In
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| Quote: Originally posted by gardenvariety | | Since you mentioned the FDA, I'll assume you're in the States. A good OTC supply of ethyl acetate is nail polish remover, at about 70ish%
concentration. One distill gets you the acetate/ethanol/water azeotrope, perhaps you can dry it and break the azeotrope from there.
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Ethyl acetate is commonly used in insect killing jars (K or Na cyanide
works a lot better, though traditionally black cyanide was used.)
Try www.Bioquip.com.
NB- Requires the onerous Hazmat Shipping charge.
[Edited on 16-1-2011 by The WiZard is In]
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smaerd
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It says here to use K2CO3 or Na2SO4 for drying ethyl acetate
http://delloyd.50megs.com/moreinfo/drying.html
So I think I'll do a drying run with K2CO3 for removal of water, then a run with CaCl2 for ethanol/isopropyl(both alcohols were in the MSDS and
ingredients).
[Edited on 16-1-2011 by smaerd]
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rrkss
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The easiest way to remove the ethanol is shake it with a saturated solution of CaCl2 and H2O. What I do is mix 20 grams of CaCl2 with 20 mL of water
and put that in a sep funnel with the EtOAc and shake for a few minutes. Then let the layers seperate and drain the top layer over some anhydrous
CaCl2 for drying. Distill the dried product and it should come over at 77 degrees. Done it many times.
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smaerd
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Thanks for the advice it really means a lot . Man at home chemistry is so much
fun!
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rrkss
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It is, I just removed grease from one of my ties using some EtOAc, saved on a dry cleaning bill :-).
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smaerd
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I'm having a devil of a time drying this stuff. I took your advice rrkss, I ended up losing maybe 30mls of the total solution so I assumed that was
the alcohol component. Still distilling over at 70*C.
Here's what I did:
Using 150mL's of distillate from non-acetone primary ingredient EtOAc nail polish remover.
first I prepared CaCl2 from CaCO3 + HCl. Filtered away contaminants(insoluble CaCO3), weighed the water solution at 33mLs it weighed approx 55grams so
I figured the experiment was done correctly(expected about a 20G yield). Evaporated CaCl2 soln down to approx 20mLs, and washed/seperated the solution
in a sep funnel. Ignorantly tried distilling immediately after, Came over at still 70*C.
Bought some Drive-way deicer(90%-100% CaCl2). Crushed pellets with mortar and pestle, dried in an over for a half an hour at 300*F/~150*C.
Approximately 50grams(my scale can be dodgy). Added the EtOAc directly to powdered CaCl2(hopefully anhydrous?) and mixed thoroughly. Some of powder
appeared to be 'dry' after several minutes.
Filtered, then ran distillation. Still coming over at 70*C?
Is the problem not using anhydrous CaCl2? How can I prepare it from CaCl2 'Pellets'? Or do I need to keep doing washes?
Edit - Upon completing the distillation there was a CaCl2 ppt in the boiling flask. I am guessing the problem here isn't the alcohol it's the water?
this website says that the azeotrope between EtOAc and water is 70.3*C. So this will be suitable for the purposes I need it for. Even though I'm OCD
about purity.
http://www.solvent--recycling.com/azeotrope_1.html
[Edited on 17-1-2011 by smaerd]
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peach
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Interesting topic.
Shame you're not in the UK, I could post you some E.acetate and some dry CaCl2.
But half the fun is making it yourself and learning along the way!
There a thread about drying CaCl2 here
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smaerd
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I cooked crushed drive-way de-icer(CaCl2 90-100% conc.) in an evaporating dish directly over stove flame for 30 minutes(stirring every 5 minutes with
a glass stirring rod). Quickly covered it with aluminum foil and allowed it to cool for 15 minutes. it lost 1.7grams of water. So it's pretty close to
anhydrous.
I then dried 80mls of impure EtOAc with 28.3 grams of CaCl2. It distilled over at 70*C. It must be a water azeotrope There can't possibly be that much
ethanol in it. I'll try a K2CO3 dry after this. If that fails I guess I'll have to deal with what I've got until I can afford to buy pure ethyl
acetate. Thanks everyone.
[Edited on 17-1-2011 by smaerd]
[Edited on 17-1-2011 by smaerd]
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The WiZard is In
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Ethyl acetate - Home Chemist Popular Science
January 1946
http://tinyurl.com/4mrt4y9 Page 199 R.
---
Byda - drying acetone has been discussed here before.
http://www.sciencemadness.org/talk/viewthread.php?tid=4488
This from the news group Sci.chem
http://tinyurl.com/47qfdvw
djh
----
From the Outer Limits of Experimentalism...
The car was 3.15 meters long, 1.15 meters tall
and weighed 308kgs... Constructed out of motorcycle
parts and with a body made of pig's blood,
chicken feathers and shellac, the Feszival
was smelly, but it worked.
The Marvellous Magyar Micocars
How Hungry circumvented Stalin and had a bit of fun
The Economist 18xii10
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starman
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Just a thought smaerd,are you sure your thermometer is sitting far enough down in the adapter?
Chemistry- The journey from the end of physics to the beginning of life.(starman)
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smaerd
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Speaking of thermometers... Mine just broke! The stupid o-ring that was holding it somehow expanded. I hear a thud, snap, and it fell right into the
boiling flask... On the bright side now I have some mercury? Gotta order a new thermometer, guess I should invest in a thermometer clamp as well.
[Edited on 18-1-2011 by smaerd]
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peach
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Mine has done something similar.
At one point, I started undoing it before removing the adaptor and it fell into a 600mm vigreux column, snapping one of the pins off.
I had that thermometer for many years and many experiments after, but it developed a split in the column; a big one. I tried freezing it and vibrating
it back into a solid column then, on closer inspection, found a hairline crack in the bulb. So that was the end of it's life and, like you have there,
I have a little blob of mercury to remember it by.
I found an old, plain test tube and siliconed it in there to amuse people with - as most people born in the last few decades haven't ever seen it in
person, and it is a very odd thing to look at and feel sliding around in the tube like liquid lead. People always want to play with it when I put it
in front of them.
Point being, you're not the first person to manage that (I know at least one other guy on here, besides myself, has done it recently).
Some lessons you only learn through experience!
[Edited on 18-1-2011 by peach]
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UnintentionalChaos
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| Quote: Originally posted by peach |
At one point, I started undoing it before removing the adaptor and it fell into a 600m vigreux column, snapping one of the pins off.
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I knew you worked on a fairly large scale, but damn!
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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peach
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I've really gone to town on the out of place units today. 
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rrkss
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if the azeotrope is water, you should see two layers form when you distill the ethyl acetate. My guess is maybe its azeotroping with the isopropylnol
since the CaCl2 should have removed the Ethanol and the water if it was anhydrous. You do decant the EtOAc from the CaCl2 before distillation do you?
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smaerd
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@peach : Awe man if it took out my vigreux I'd be very upset(esp a 600mm one). Sounds like I got away from this pretty clean. RIP to our thermometers
hehe. Served us well. Your right this mercury is pretty neat .
Besides this give me an excuse to have a thermometer clamp.
WAIT? Is that your picture or did you digitally modify mine? haha edit - oh I get it you took a picture of your Hg sample overtop of your screen haha.
@rrkss: Yes I was decanting prior to distillation and doing a quick filtration. There were no obvious layers in any of the distillates. When I added
CaCl2 though and shook the whole solution turned a murky calcium white/gray. Which isn't really typical of other solvents I've dried. Normally the
drying agent wouldn't linger in soln for more than a few moments. Perhaps a finer filtration will help, I'll try a vac filtration with proper paper
instead of gravity filtration and coffee filters
[Edited on 18-1-2011 by smaerd]
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UnintentionalChaos
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I see your mercury and raise you more mercury.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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smuv
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Bring IT!
This thing is gonna go viral.
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peach
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