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Amy Winehouse
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Sodium Ethyl Sulfate
Hi SM how are you?
Great! me too!
I want to discuss this section of a widely known synthesis for nitroethane:
[There is already a thread on nitroethane synthesis, but the question I have is NOT regarding nitroethane]
"113 parts by weight of sodium bisulfate and 20 parts by weight of pure grain
alcohol are combined in a flask and brought to boiling upon which time the sodium
bisulfate crystals disappear and sodium sulfate forms.
When the reaction has been completed, the flask is immersed in an ice bath and vigorously stirred until the tempurature rapidly goes below 32.3C. The
formed sodium sulfate is thus filtered out leaving an anhydrous ethyl hydrogen sulfate/ethanol mix. The excess ethanol is distilled off, and the ethyl
hydrogen sulfate is neutralized with an appropriate quantity of sodium carbonate leaving sodium ethyl sulfate. Simple... thats all there is to it!
The secret to how it works is the excess
sodium bisulfate when rapidly cooled below 32.3C forms the decahydrate, or Glaubers salt, and this sucks the water out of the reaction"
Sodium ethyl sulfate is needed for that Nitroethane reaction, but I just want to discuss the Sodium Ethyl Sulfate, specifically the part where i i suck at life.
Note:I used 75.5% grain alcohol because my local liquor stores ALSO suck at life but i figured the decahydrate
would suck all teh h20s up.
Anyway, I nuked the ethanol/sodium bisulfate concoction in a RBF til it boiled and then vigorously stirred in an ice bath, but when the time came for
step "thus the sodium sulfate is filtered out leaving an ethyl hydrogen sulfate/ethanol mix" I ran into a problem. What was left in the flask was a
bunch of chunky gunk(i assume sodium sulfate) and a VERY small amount of liquid. I tried dumping it through filter paper and all the liquid stayed
inside the chunky stuff.
What am i doing wrong besides being a Huge Noob? Should I use a buchner funnel to suck the liquid off of dat shit at
the pump?
Thanks SM!
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Foss_Jeane
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Looks like a quote from an old source (archaic terms). I read "pure grain alcohol" to mean anhydrous ethanol. 151 proof vodka is far from
pure, and should have been distilled to get 95% ethanol, and then dried to remove the remaining water. That's way too much water to remove
with just the NaHSO4.
If you can't set up to distill and dry ethanol, you can't do this, and shouldn't even be trying.
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Amy Winehouse
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No man pure grain alcohol is just 95%. Im distilling it to get 95% right now, i dun figgered it was too much to remove with NaHS04 it doesnt need to
be anhydrous the sodium sulfate does work when it turns into the salt.
But obviously absolute etoh would be ideal...is there a way to do it without a vacuum dessicator? I dont have one.
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Bot0nist
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I have had some luck using anhydrous copper sulfate to dry ethanol. I don't think it fully breaks the azeotrope, but it does remove some water from
95% ethyl alcohol (Golden Grain) when distilling.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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Amy Winehouse
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sweet thanks man, ill give that a try.
 Distilling it to 95% is taking daaaaaays
#impatience
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Bot0nist
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Are you distilling from vodka? When I distill from white wine I find that salting the wine a bit with NaCl really helps by raising the BP of the water
in the solution, allowing for a better fraction of alcohol to come over. It doesn't take much salt to notice this effect.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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Amy Winehouse
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Okay man, I like your signature a lot.
Im trying the NaCl im distilling from Grain Alcohol (Everclear).
Anyway, once i do boil the NaHSO4 with the EtOH whats the best filtration method for the sodium sulfate?
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xwinorb
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Hi Amy Winehouse :
I was considering using this method to make nitroethane, and looks like it does not work as stated.
Please see this thread, I started it :
http://www.sciencemadness.org/talk/viewthread.php?tid=13343&...
If you want nitroethane ( looks like not exactly what you want ) , better make ethyl bromide, then react in DMF with sodium nitrite.
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Amy Winehouse
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Oh okay, i DO want nitroethane. DMF is pretty tough to get, does substituting it for dimethyl sulfoxide work?
And someone in your thread [I apologize for not finding it the search i did was for sodium ethyl sulfate specifically] suggested using sulfuric acid
and ethanol, but that just produces ethyl sulfide?
[Edited on 3-11-2011 by Amy Winehouse]
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Bot0nist
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Did you see Antancho's (sp) thread?
[Edited on 3-11-2011 by Bot0nist]
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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Nicodem
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Thread Moved
3-11-2011 at 10:17 |
xwinorb
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More info
Some more information for you then :
I am aware of the Antoncho way to make nitroethane, I think it is more dangerous and prone to error and low yielding. Uses high temperature also.
The DMF is relatively easy, take care with the work up, not dangerous if not distilling the nitroethane. You might get low yields for not doing a good
workup. DCM works well as a solvent here ( I mean DCM, not DMF, for the work up, not for the reaction )
No, you CAN'T use DMSO, instead of DMF, it does not work.
Like most other methods I am aware of, including Antoncho's, it uses a LOT of solvent and nitrite to get a relatively small amount of nitroethane.
I made 80 g of ethyl bromide, at circa 75 % yield. From this one I was able to make circa 30 g ( a bit less ) of nitroethane. Yield here at circa 50
%.
I did not distilled the nitroethane, instead I distilled out the DCM as much as I could. First with aspirator vacuum, then w/o.
Slight yellow color, good smell, transparent, and worked very well. It smells a bit like airplane model glue.
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Amy Winehouse
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I have DCM, just not DMF. Where do you get your DMF? I live in America.
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xwinorb
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Have emailed you, please check it.
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aaparatuss
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What of the sulfamic acid technique, i hope to try this soon.
i bet the dry distillation of ammonium ethyl sulfate ala
"1.5 mole sodium nitrite (103.5g) is intimately mixed with 1 mole of sodium ethyl sulfate (158g) and 0.0625 moles of K2CO3 (8.6g). The mixture is
then heated to 125-130°C, at which temperature the nitroethane distills over as soon as it is formed. "
by Aurelius (format & minor edits by metanoid)
works it must be tried at least.
second ... getting 3A or 4A molecular sieve beads is not a hassle, drying alcohol is the least of our worries.
third.... evil lurker should be trust worthy ...cool the mixture faster i have not tried this method ither....
[Edited on 4-11-2011 by aaparatuss]
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madcedar
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Alteration to the method of US Patent 3024263
Preamble:
Sodium Bisulphate (anhydrous) mw=120 mp=315
Sodium Bisulphate (mono hydrate) mw=138 mp=58.5
ethanol mw=46 density (of 95%)=0.789
one mole of 95% ethanol weighs 46/0.95=48.4g (48.4/0.789 = 61.4ml)
water mw=18
one mole of 95% ethanol has (0.05*1/0.95) * (46/18) = 0.134 mole water
2NaHSO4.H2O + C2H5OH <=> C2H5HSO4 + Na2SO4 + 3H2O (87% yeild)
113 parts + 20 parts -> 45.3 parts
Na2SO4 can adsorb 10 moles of water => 7 mole to play with.
Altered Method:
The original patent method uses 20 parts of 95% ethanol to 113 parts of sodium bisulphate. Anyone who has tried this knows that that amount of ethanol
hardly wets the sodium bisulphate. Looking at the reaction equation it is clear that ten times the amount of ethanol can be used while only 50% of the
Na2SO4 water absorbtion capacity is used.
Next thing to note that the monohydtate of sodium bisulphate melts at about 58 degrees (it also turns stainless steel black - so use glass).
This is what I did: My sodium bisulphate came from a swimming pool supply store so I heated some sodium bisulphate up to find out if it was anhydrous.
Since it didn't melt at about 70 degrees I assumed it was anhydrous. So, for one mole of room temperature anhydrous sodium bisulphate I added 18 ml of
water. This was then heated until it melted. Then I dumped in about 200 ml of hot ethanol (about 70 degrees) and instantaneously the two liquids
formed a solid mass of what I assumed to be sodium sulphate. I didn't reflux at all, I just let the whole lot cool and then filtered off the solid
(sort of squeezed it through an old T-Shirt). When I added sodium bicarbonate to the filtrate there was a lot of hissing going on and for a long time
as I needed to add a lot to get the pH to above 7.
That's as far as I went with the reaction.
Other things to know:
A solution of sodium ethyl sulphate can be heated and reduced without destroying the sodium ethyl sulphate as long as the pH is kept above 7. I read
somewhere (maybe on this forum, and very sorry because I don't have a reference) that sodium hydroxide can not be used to raise the pH, it must be a
carbonate. Now I don't know if that's true or not.
I hope someone out there double checks what I did and comes up with a way to isolate sodium ethyl sulphate.
To get a better yeild of nitroethane the sodium ethyl sulphate must be wet distilled as dry distallation with sodium nitrite gives close to 6% yeilds.
See https://www.sciencemadness.org/whisper/viewthread.php?tid=4711&page=2#pid192565
Cheers
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Nicodem
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So now we have another thread for the too lazy to UTFSE to get engaged in idle talk. Can you now all please stop and read Antoncho's thread already?
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madcedar
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You as a moderator should have stopped this bullshit thread at post #1 if you care so much about it. As for finding stuff, that's what search engines
are for and information can be anywhere and everywhere - a computer will find it and display a nice list of results for us poor humans.
The problem with this site is that the search engine is useless. For example, search (limit to subject only) for "nitroethane" and then search for
"nitroethane again" and see the difference in results! To search this site properly us users have to use Google as follows: "nitroethane
site:sciencemadness.org".
There is also another huge problem with creating a single thread on one subject and that is that the thread becomes too long to be of any use at all,
just look at the sticky potassium thread, it's next to useless... mainly because of this sites next-to-useless search engine. People ask the same
questions many times over in the same thread because no one has the time to read it from start to finish. So next time you want to waste your time and
tell someone to UTFSE YDC (you dumb c*nt) think first okay. Do your job and delete the thread at post #1 if you care so much.
[Edited on 5-11-2011 by madcedar]
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Bot0nist
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Madcedar, I agree that the search engine isn't the best. It would work better if more people would make a meaningful subject for their posts that
contain useful information. For instance, instead of naming your post "Alteration to the method of US Patent 3024263" which is detailed and accurate,
you could have named it something that people who are looking for the info you posted might search for.
Nicodem is doing his job. He is trying to encourage us to read and add to existing threads, rather than start a new one on the same topic. This also
would make the FSE a little more usable. As far as calling the SuperMod a dumb cunt, well , I'm not touching that one.
Good luck.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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madcedar
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Thank you for your mature and erudite reply. Sorry for my silly abuse but it wasn't directed at Nicodem, I have read many of his posts and he is (I
assume he is a he) very intelligent. It's just that when I see UTFSE in a post I assume the real connotation is UTFSE YDC and in this particular case
I felt it was directed at me. No harm done.
Cheers
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dann2
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UTFSE should be changed, for the ScienceMadness Board, to DBUTFSEAIIAFU (dont bother using the f&*^%$* search engine as it is absolutely
F&^%*$% USELESS)
When the 'search' facility button in pressed it should take you to a page that tells you how to google the sci board board using google
IE. in google box you type 'string to be searched' :site www.sciencemadness.org
or put a google search box at the top of the board for all and sundry to use.
Perhaps there is a reason why this is not as straight forward as it would seem (cannot search refs??) etc
My 2 cents worth
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chucknorris
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Is there even a theoretical risk that when producing sodium ethyl sulfate using sodium bisulfate and ethanol that diethyl sulfate could be formed
during the process?
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slinky
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The search engine works fine for me. It's the reason I have so few posts. Nearly every question I've ever had has already been asked an answered.
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Formalomaniac
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Hi bees , as i read i see you dont know how to andle the so needed sodium salt.
Jus try this denaturated alcool(ethanol,32 gr) 40ml ,15ml of sulfuric acid where placed in a 250 ml rbf under reflux (below 140deg.) for at least 45
min, a solution of sodium carbonate (40g/100 ml h2o,prepared and shaken with a magic bullet lot of time is saved here ) wait to the sodium carbonate
solution becoming clear,and neutralise first youll see sodium bicarbonate precipitate out as it is almost insoluble in ethanol ,filtrate out,let the
solution concentrate on low heat,again youll probably have to filter to remove another crop of bicarbonate crystals,between each filtration add some
mdthanol or ethanol to force precipitate out the carbonate leaving alone the sidoum ethyl sulfate as eh is very soluble in heated methanol at the end
you should be left with a alcoolic solution of sodium ethyl sulfate(when no more bicarbonate precipitate from the alcoolic solution).Reduce this
mother liquor but beqare when it will start to boil hard projecting drips of the solution its time to recrystalize,cool down a bit add 10-20 ml
acetone and pour on a pyrex glass,it was for me some of the nicest crystals on earth they look like humans hairs during crystalizing(or more needles
like to others) voila the remaining product for this batch after purification is 14.33g of sodium ethyl sulfate. PS: if you heat more longer youre
mother liquor the bicarbonate will convert into carbonate much more easy to purify the product as it is completely insoluble in acetone and anhydrous
alcool.
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Fantasma4500
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Hi bees- As i read, i see you dont know how to handle the needed sodium salt. (NaHSO4)
Try this: denaturated alcohol (ethanol,32 gr) 40ml and 15ml of sulfuric acid were placed in a 250mL RBF under reflux (below 140deg) for at least 45
min.
A solution of sodium carbonate (40g/100mL water, prepared and shaken with a magic bullet (lots of time is saved here)
Wait for the sodium carbonate solution to become clear, then neutralise.(?)
First you'll see NaHCO3 precipitate out as it is almost insoluble in ethanol, filter out, let the solution concentrate down on low heat, again you'll
probably have to filter it to remove another crop of NaHCO3 crystals. -Between each filtration add some mdthanol or ethanol to force precipitate out
the carbonate leaving alone the Sodium Ethyl Sulfate as it is very soluble in hot methanol.
At the end you should be left with a alcoholic solution of Sodium Ethyl Sulfate (when no more bicarbonate precipitates from the alcoholic solution).
Reduce the solution but beware when it starts to boil hard, projecting drips of the solution(?help) its time to recrystalize.
Cool down a bit and add 10-20 mL of acetone and pour into a glass pan.
It was for me some of the nicest crystals on earth, they look like human hairs during crystallization (or needles). Voila! The remaining product for
this batch after purification is 14.33g of Sodium Ethyl Sulfate.
PS: if you heat the solution longer the bicarbonate will convert into carbonate much more easily, to purify the product as it is completely insoluble
in acetone and anhydrous alcohol.
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Texium
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Did... did you just bump a 6-years-dead thread just to partially correct the (admittedly, atrocious) spelling and grammar of the previous poster?
...well, I guess I've seen worse ways to revive old threads. Here, I'll take it one step further!
| Quote: |
Hi, fellow chemists. As I read, I see you don't know how to handle the needed sodium salt. Try this: denatured ethanol, 32 g (40 ml) and 15 ml of
sulfuric acid were placed in a 250mL RBF under reflux (below 140ºC) for at least 45 min. A solution of sodium carbonate (40 g/100 mL water), was
prepared and shaken with a Magic Bullet (lots of time is saved here). Wait for the sodium carbonate solution to become clear before using it to
neutralize the ethanolic sulfuric acid.
First, you'll see NaHCO3 precipitate out, as it is almost insoluble in ethanol. Filter this out, then let the solution concentrate down on
low heat. You'll probably have to filter it again to remove another crop of NaHCO3 crystals. Between each filtration, add some methanol or
ethanol to force precipitate out the carbonate, leaving the sodium ethyl sulfate in solution, as it is very soluble in hot methanol. At the end, you
should be left with an alcoholic solution of sodium ethyl sulfate (when no more bicarbonate precipitates from the alcoholic solution).
Concentrate the solution. Once it starts to boil hard, projecting drips of the solution, it is time to recrystallize.
Cool the solution and add 10-20 mL of acetone and pour into a glass pan. It was for me some of the nicest crystals on earth, they look like human
hairs during crystallization (or needles). Voila! The remaining product for this batch after purification is 14.33g of sodium ethyl sulfate.
PS: if you heat the solution longer, the bicarbonate will convert into carbonate. This makes it much easier to purify the product as carbonate is
completely insoluble in acetone and anhydrous alcohol. |
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