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UnintentionalChaos
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Quote: Originally posted by Sedit  |
You ask about 95% EtOH being used but its just not going to work. It is sensitive to hydrolysis and a drying tube should be employed during reflux in
the first place when using anhydrous reagents. Using wet EtOH will damage the synthesis from the ground up. Deicing solution in the states anyway is
Ethylene Glycol and EtOH. MgSO4 and a distill should yeild a rather clean anhydrous EtOH for the synthesis as its what I use for EtBr synthesis in the
past and that went rather smooth.
Hope this helps a bit. |
Indeed, I can confirm the moisture sensitivity of the ammonium alkylsulfate. A few crystals of the methylsulfate dissolved in a few drops of water
yield no precipitate with SrCl2 initially but forms a cloudy solution after sitting for only a few minutes at room temperature. The decomposition is
self-promoting as the acidic ammonium bisulfate product promotes hydrolysis of more methylsulfate as long as water is available. Heating can only make
it worse. Consider using anhydrous reaction conditions if possible.
[Edited on 3-27-11 by UnintentionalChaos]
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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no_dream
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small research for NaEtSO4 routes
Optimization of sodium ethylsulfate synthesis
Some experiments were conducted on this problem.
Materials used: acid - 96% pure sulfuric acid, alcohol - 99% ethanol with 0,1% MEK and bitrex, CaCO3 - technical grade., Na2SO4 - anhydrous., Na2SO4 -
ordinary soda, decahydrate
The scale was 0,3 mol and five samples were prepared.
Sample 1: according to US 3,047,604
17ml acid was added to 18,5ml of alcohol with shaking. After cooling, 8g of dry sodium sulfate was added. The mixure was slowly added with good
stirring to an excess of calcium carbonate suspended in water(approx. 25g in 150ml). The solution was vacuum filtered to obtain a clear, neutral
liquid. Some phenolphtalein indicator was added and the calcium ethylsulfate was converted to the sodium salt. The formed calcium carbonate was
weigted to determine HEtSO4 content. Saturated soda was added until slightly alkaline - pink. PH approx 9 to 11. The suspension was again filtered,
and a 25ml sample evaporated to determine the mass of dry NaEtSO4:Na2CO3 mixture. Another sample (25ml) from this mixture was treated with an excess
of calcium chloride solution to determine the carbonate content in the liquid. The purity and concentration of final product was calculated..
Sample 2: as per sample 1 but without the sulfate
Sample 5: 3:1 alcohol to acid with sodium sulfate
17ml acid to 55,5ml of alcohol. After cooling 10g sodium sulfate added with occasional shaking. Neutralization as before.
Sample 4: according to sample 5 but without sulfate
Sample 3: according to [1]
55,5 ml alcohol was added to 17ml acid, then refluxed in a water bath two hours. After cooling, the liquid was diluted with 100ml water and CaCO3
suspension was added in excess until neutral and no gas evolved. The neutralization produced much foam and aerosol. A small loss was due to
overfoaming.
Results:
No.1:56,5% HEtSO4 of theory, sample purity 69% NaEtHSO4 - error due to splattering when evaporation. 13,3 % of theory of NaEtSO4 calculated from dry
mass
No.2:54,6% HEtSO4 of theory, purity 71,7%, 12% of theory of NaEtSO4
No.3:73% HEtSO4 of theory, purity 81%, 36% of theory of NaEtSO4
No.4:76,3% HEtSO4 of theory, purity 53,5%, 10% of theory of NaEtSO4
No.5:86% HEtSO4 of theory, purity 68,7%, 24% of theory of NaEtSO4
The dry weight of the samples was less than the calculated NaEtHSO4 content, so there must be an error in the process
The best method according to EtHSO4 yield was 5, for the total NaEtSO4 yield method 3.
Notes:
a) The best purity product of archieved if the neutralisation, or at least the last part is conducted using calcium carbonate. The resulting liquid is
neutral and contains only the soluble Ca(EtSO4)2.
b) Only a slight excess of soda to phenolphtalein is required during evaporation to keep the solution alkaline. Too much soda added makes product
impure with sodium carbonate.
c) An excess of alcohol is preffered during the HEtSO4 production. Good stirring is required. Exernal cooling is not needed, some of the alcohol boils
off. The alcohol should be added fast. Acid and alcohol cooled in a freezer are preferable. It is not needed to notice the exothermical nature of the
reaction. The neutrallization produces only slightly heat.
d) All samples above were leaved overnight before neutralization except No.1.
e) Sodium sulfate produced no temperature rise opposed to the patent. The mixture was shaken occasionaly and then leaved. A cake formed on the bottom,
easing decanting the liquid. Some losses are inevitable.
Ethanol recovery is possible, but was not practised because of the volumes of solutions.
Full scale 3mol test of method 5:
170ml acid added to 555ml alcohol. After cooling to slightly warm to hand, 100g anhydrous sodium sulfate added, strirring continued until cold. This
was about 4 hours. Then the stirring was discontinued and sulfate let settle. The whole mix was vacuum filtered to minimize losses, but decanting
would suffice.
The combined neutralization was proved not to be good, because of delay in ph change. First about 70g slaked lime was suspended in a liter of water,
then about 100mls of mixed acid added. Then the mixture become slightly acidic, so about 150g of CaCO3 was added. All of the acid mixture was slowly
added with high power stirring with a hand blender (motor with a stick and a blade on the end). Then another half liter H2O added and everything
filtered through a cloth and then with vacuum. The gas evolution from the neutralization proved no problem as stirring was vigorous.
The amount of soda was determined and an solution was added to the calcium ethylsulfate. After filtering, a calculated amount of 1,84 mole of ethylNa
sulfate was in 2625ml solution. This is 61 per cent of theory. After evaporation and cooling crystal formed, probably of soda. They were filtered ant
thrown away. Total volume 360ml, density 1,3.
A test run - 142g NaNO2, 17,6g K2CO3, 90ml H2O, some silicone antifoaming agent and the solution obtained above was made. At the end water was added
too.
Temperature was controlled 130-125C, but sometimes it went to 120-115 after adding too much solution.
Workup: distilate (approx. 500ml) was half saturated with salt and CaCl2 (foaming!). After separation, extraction of aqueous with DCM, drying on CaCl2
and adding charcoal, a fractional distillation was run.
Result: 44mls of EtNO2, distilled 112-116degC. Last drops made distillate little cloudy.
0,618 mol from 1,84 mol ethylNasulfate = 33,6%.
20,6% of theory overall yield to acid, 6,86% on alcohol.
Compared to an earlier attempt with 1:1 EtOH:H2SO4 and sodium sulfate, where from 2mol
acid and alcohol the yield was 17ml, 226mmol, 22,6% on NaEtSO4.
Calculated 11,3% total yield to acid or alcohol.
Not much improvement.
Conclusion: It seems the yields cannot be raised much. The desseigne process has a maximum of about 50%, so better methods must be
tried for the NaEtSO4. Some research was made and it might be useful to research deeper. Also the sodium bisulfite and direct
neutralization(HEtSO4+Na2CO3) should be examined more.
References:
US patent 3,047,604
[1] S. LEVY, Anleitung zur Darstellung organisch-chemischer Praeparate., Stuttgart 1895
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Thor
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Can anyone explain the use of the Potassium Carbonate in the final reaction step? Writing out the equation, I can't see it taking part in the
reaction. The only reason I can think of is to adjust the pH?
The reference posted is in French, and i'm a bit rusty..., google also turns up lots of examples of the reaction, but nothing on the use of the
carbonate.
Edit: Possibly to hydrolyse the Sulfuric ester?
[Edited on 25-9-2011 by Thor]
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Hexagon
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| Quote: Originally posted by Thor | Can anyone explain the use of the Potassium Carbonate in the final reaction step? Writing out the equation, I can't see it taking part in the
reaction. The only reason I can think of is to adjust the pH?
The reference posted is in French, and i'm a bit rusty..., google also turns up lots of examples of the reaction, but nothing on the use of the
carbonate.
Edit: Possibly to hydrolyse the Sulfuric ester?
[Edited on 25-9-2011 by Thor] |
AFAIK, the potassium is there to make some kind of euthetic and help lower te melting point of the mixture.
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chucknorris
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Ok I did make some half a kilo of ethyl sulfate recently.
What I did was that I measured about 1:1 in weight sodium bisulfate(pool grade is ok, if it wont melt at 60C, add 1:10 ratio of water and heat up to
110c or until it is fully liquified) and ethanol(95% commercial denatured grade goes well, I explain this later) and heated up them both in different
pots. The bisulfate should be heated up to 70C and make it fully liquid, same temp is good for ethanol.
Then one should slowly drip the ethanol into the liquid bisulfate. It will instantly turn into white cake of sodium sulfate and the reaction is so
exothermic it will cause the ethanol to boil and vaporize so a reflux column is a good one.
One MUST shake or stir the reaction vessel vigorously to avoid formation of sodium sulfate cake. If it is left untouched, it WILL form a layer in the
reaction vessel between the ethanol and the liquid bisulfate and this can lead into major catastrophy which happened to me once. When there is ethanol
in the flask and the cake layer is carefully broken, the two will mix up instantly, causing large amounts of ethanol being vaporized so that this
volcano eventually reached the roof of my laboratory measuring 3 meters of height. A metallic stirrer rod or something ultra-heavy duty is mandatory
for this project, or then just after every 5ml addition of ethanol, take the reaction vessel and shake it in your hands violently in order to break
the cake before it gets too heavy to be broken without steel rod.
Ok then, when all the ethanol is mixed, heat the vessel for about 15mins for full power with reflux on, and then carefully insert it into cool bath
and wait for the core temperature to decrease below 30 degrees. Then you can add 100-200ml of extra ethanol just in case to wash the formed ethyl
sulfate residue from the sodium sulfate cakes, and then pour everyting into filter and acquire a slightly yellow liquid.
Then boil up this liquid up to 130 degrees of temperature maximum, and wait for the boiling to cease so that all ethanol is evaporated, a yellow oily
liquid is being left in the flask. All unreacted ethanol will be retrieved if reflux condenser is succesfully used, usually with 1:1 ratio this is
around 1:4-1:3 of used ethanol in return. The ethanol acts as an solvent for the ethyl sulfate, so do not try to scale it down, you will only lose
ethyl sulfate.
Ok now you will understand what makes the denatured ethanol OK for this project.
Measure the weight of the ethyl sulfate freebase and get 1:1 ratio of sodium bicarbonate or baking soda and dump it into, vigorously stirring. The
stuff will hiss and it will swoll up so use at least 5 times larger vessel than the volume of the liquid. CO2 is formed in large amounts. This
reaction takes some 10-15 minutes, and then you shall just leave the stuff there and come back after 1 day and you will see that a fine white paste
has formed in the bottom, and there is yellow oily layer on the top.
This oily layer is the residue of the denaturing agents and other random goo and shit that is left from the reaction. We do not want this garbage in
future, so do this: add at least 2 times the volume of anhydrous acetone(water is bad, it dissolves the sodium ethyl sulfate and you will lose it) and
pour the stuff into filter. After everything has been filtered, add 1 times the volume more acetone. The acetone will dissolve and wash all the liquid
shit off from the sodium ethyl sulfate, and only a pure sodium ethyl sulfate and possibly residues of sodium bicarbonate are left in the filter. Let
the mass dry and scrape it into container. You should have pure white fine powder.
If the sodium bicarbonate must be avoided and only 99% sodium ethyl sulfate is wanted and the actual amount of denaturing agents is not known, a pure
anhydrous ethanol must be used. Other way, which will cause about 5% yield loss but can be done with commercial detanhol is to add 5-10% LESS sodium
bicarbonate by weight into the ethyl sulfate freebase. This will leave some freebase unreacted and it will go through the filter into the waste
acetone denatured goo shit, but that way you'll get absolutely no sodium bicarbonate residues into your sodium ethyl sulfate.
Oh, and the yields? Of course. For 4 different runs with only minor differences in the process(no cold dumping, vigorous additon of ethanol(and huge
losses of ethanol by vaporization), I managed to get around 45% yield from the sodium bisulfate by weight. So 1kg of bisulfate equals to about 450
grams of ethyl sulfate freebase.
[Edited on 3-5-2012 by chucknorris]
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Amy Winehouse
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Some words about the Sulfamic Acid route:
Marvelous! Riveting! wurks gud.
Alcohol and sulfamic acid are cheap as dirt and the alcohol I used was between 96-98% ethanol, thats right - not anhydrous. I've run this
reaction 5-6x, and heres some logistics to keep in mind/things that might have gotten lost in translation if anyone is interested and wants to try
this route, which I highly recommend doing.
1) A drying tube with CaCl2 must be used during the entire duration of the alcohol/sulfamic acid reflux period as even slightly
hydrated alcohol will become anhydrous as the reaction proceeds (at the cost of some product) and it will suck up water and ruin everything(my first
few fuckups, et al; 2012)
2) Don't wait for everything to crystallize before neutralizing, a)you won't get it all b) hydrolysis tick tock tick tock; just add a little less
solution than theory (0.5 eq versus sulfamic acid) directly to the RM after the alcohol is gone and proceed from there, its fine if you overshoot
3) When evaporating to spg, put in the freezer and let sit for 20 min or so and gravity filter, collecting a sample of these droplets when testing.
Even if it's not hot, there could still be dissolved solids giving you incorrect density reading(and that will clog up your addition funnel later on).
I don't think it can go past 1.35 g/ml, any evaporation passed that and you're precipitating product.
4) Just use regular old NaCl to separate EtNO2 from H2O, CaCl2 will cause it to foam up nasty-like.
5) I think Russian conditioners must be different than other places, but please don't use random conditioner as an anti-foaming agent.
Simethicone(polydimethylsiloxane) is cheap and won't make you're distillate smell fruity or tropical.
Good luck!
"I'm too drunk to taste this chicken"
-Colonel Sanders
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roamingnome
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hashing out this ammonium ethyl sulfate situation and i believe the nomenclature is a miss.
Sulfamic acid reacted with ethanol will potentially form ethylsulfamate, or sulfamic acid ethyl ester ,
the ammonium is not a free moving ion as in typical salts. this doesn't really matter i suppose as long as the isolate effects the reaction of
nitrite the same.
It seems isolating the dry compound is not favored but the compound is left in alcohol of a certain s/g
Is this then mixed with the carbonate and nitrite like that?
US patent 2785196 actually gives the melting point of
of ethyl sulfamic acid as 170 C
does it react similar?
im struggeling to separate the the ethyl from unreacted sulfamic acid .
$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$&$
And now time for a special update
United States Patent 4469841
"During baking, of the order of about 121° C, the ethyl N,N-dimethylsulfamate ##STR1## sequentally undergoes the following reactions. The sulfamate
undergoes a molecular rearrangement in which the ethyl radical of the ester migrates to the nitrogen atom, forming a betaine ##STR2## The betaine
adsorbs water to form a trialkyl ammonium bisulfate salt ##STR3## It subsequently decomposes to volatile dimethyl ethyl amine and sulfuric acid. "
Well its seems a similar ester does lose the ethyl as a radical which is good i think.
Now what is the temperature of reaction of nitrite, carbonate, and ethyl sulfate?
Attachment: US2785196.pdf (158kB)
This file has been downloaded 2392 times
[Edited on 1-8-2012 by roamingnome]
[Edited on 2-8-2012 by roamingnome]
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anomolous
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Can someone explain why Antoncho first neutralized the ethylsulfate with Lime and then with sodium carbonate? Couldn't the sodium ethyl sulfate be
formed by neutralizing ethylsulfate with sodium carbonate and skipping the calcium hydroxide step? Based on my trenslation of the original French
article, this is exactly what they do. What is the purpose of using the Lime?
I've been trying a bunch of nitroethane synths out. I did repeat this process with some success but it needs to be streamlined to improve yields as I
did not get as much as Antoncho. Check out my posts in the Nitroalkane thread if interested in my attempts using 2-bromoproprionic acid. I definitely
need help there. If Antoncho is around I'd love your opinion.
Peace.
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no_dream
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Because the French article uses oleum for the esterification of ethanol. So the free SO3 reacts with the water formed in the reaction and the yield of
ethyl-sulfuric acid is close to theoretical.
But when using sulfuric acid and 1,6eq of ethanol, the conversion is about 50%. Don't believe it can get better using sodium sulfate.
Direct neutralization will produce an mixture of Na ethyl-sulfate and Na sulfate. Maybe too much sodium sulfate will interfere with the reaction. Much
sodium sulfate is produced by the final reaction with nitrite, but maybe it could work. Try it out.
Using an calcium salt (carbonate is better than hydroxide) for neutralization gives calcium ethyl-sulfate and CaSO4. The filtered liquid contains only
the ethyl-sulfate. Reacting with sodium carbonate precipitates calcium carbonate and leaves practically pure Na ethyl-sulfate in the solution.
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anomolous
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Ah, thanks. I did try to neutralize with only Na2CO3 and did get some nitroethane but, you're right, yields weren't as good as when I neutralized with
Ca(OH)2 (all I have on hand). If anyone is interested I will post the results.
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anomolous
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Experimental 1: 300 mL of 96% H2SO4 was carefully added to 600 mL of ~95% ethyl alcohol in a 1000 mL Erlenmeyer. 250 g of anhy. NaSO4 was added and
the mixture placed into the fridge and then into the freezer to cool to about 10C. The hydrated sodium sulfate was filtered leaving ~800 mL of
ethylsulfate/alcohol solution . The solution was treated with sodium carbonate until a neutral pH of 7 was reached. Blue indicator paper turned
slightly pink and red paper turned slightly blue at this pH. The neutral solution was cooled to near 0C and the precipated salt (mostly sodium
sulfate) was filtered. The filtered solution was distilled and about 200 mL of alcohol was collected. The residue was filtered again and evaporated in
a pyrex dish until a skin began to form, at which time the heat was turned off and the solution allowed to cool on the hotplate. A lot of salt,
consisting of a mixture of sodium sulfate, carbonate, and ethyl sulfate, precipitated. This salt was saved to be analyzed and possibly used to produce
more nitroethane. The filtered liquid, about 292g/240 mL, and a density of 1.21 g/mL was further distilled and more salts filtered yielding 210 g/155
mL (= Density of 1.35 g/mL). This close to the density of a 50-55% solution of ethyl sulfate, according to the Antonch and Desseigne figures. Upon
sitting further, overnight, the solution crystalized further, leaving 164 g/123 mL (Density = 1.33) of sodium ethylsulfate sol. A 55% (by weight)
solution of 210 g ethylsulfate sulfate sol. would contain 210 g * .55 = 115.5 g. The molar mass of ethyl sulfate is 148.12, which means we
hypothetically had about 0.77 moles of ethyl sulfate in solution. I will react this solution with a molar ratio of sodium nitrate—about 53 g. 7 g of
potassium carbonate (~6.9% based on 210 g sodium ethylsulfate sol.) will be used and 6 g of cetyl alcohol hair-conditioner. e
6 g of hair-conditioner was added to a 500 mL flask equipped for distillation, followed by 7g of potassium carbonate dissolved into 27 mL of water.
Stirring is activated and 53 g of sodium nitrite is added. The oil bath is heated to 155C and the sodium ethylsulfate sol is added dropwise. The
addition was stopped because it took some time for distillate to occur then continued at the rate of distillation. After the addition 100 mL of water
was added dropwise and the distillation continued to make sure all of the nitroethane distilled over. About 150 mL of distillate, a mixture of water
and yellow globules of nitroethane, was collected. This was extracted with ether (3 x 50 mL). The ether was removed by distillation, and the residue,
maybe 15 mL, was saved to be further purified once more is collected.
Experimental 2: 600 mL of 95% ethyl alcohol was carefully mixed with 300 mL of 96% sulfuric acid. A titration was done showing it was a 9.26 molar
solution. 840 mL required 7.78 mole Ca(OH)2 is required to neutralize this solution so 575 g of Ca(OH)2 was mixed with 2000 mL of water in a large
pitcher and the 840 mL of ethylsulfate/alcohol solution was carefully added to this with stirring. After the the ethylsulfate solution had been
reacted with the Ca(OH)2 another 500 mL of water was added to assist in extraction and filtering as the mixture was very thick. The CaSO4 formed was
filtered through clothe and then through filters until the solution was clear, resulting in 1970 mL of CaEtHSO4 solution. 100 mL of this solution was
reacted with an excess of Na2CO3 and the chalk vacuum filtered, dried in an oven, and weighed (4.4 g) to determine the amount of Na2CO3 needed for
neutralization. In this case 0.87 mol or 91 g of Na2CO3 (4.4 g/100 = 0.044 mol; 0.044 mol x 19.7 = 0.87 mol; 0.87 * 106 = 91 g). I used 92 g as an
excess was recommended. The resulting solution had a pH of 9.4 and turned red indicator paper a vibrant blue. The mixture was vacuum filtered. Do not
try to filter all of the CaCO3 all at once unless you have a gigantic filter because it will not fit. I had a fairly large Buchner and did half of the
mixture; I rinsed the chalk, emptied the Buchner funnel, changed the filter, and then did the other half. The filtrate was refiltered by gravity
filtration until clear and then evaporated on a pyrex cakepan with a fan blowing over it overnight. CaCO3/NaEtHSO4 salts precipitated during the
evaporation. These were filtered and saved for further experimentation and the filtrate, 256 g/200 mL (Density: 1.28), was used in the next step. It
will be assumed that 0.87 mol or 124 g of sodium ethyl sulfate is in solution and this will be reacted in a molar ratio to sodium nitrate (58 g). To a
500 mL flask with three-neck adapter, equipped with mechanical stirring, for distillation, and with an addition funnel, was added a squirt (5-7 g) of
cetyl alcohol hair-conditioner, 30 mL of water, and 8 g of potassium carbonate. This was mixed, placed into an oil-bath and the oil-bath heated
quickly to 155C with occasional stirring. Once the oilbath reached 155C the addition funnel was charged with the NaEtHSO4 solution and the addition
began. The addition was carried out very slowly at first and then accidently nearly all of the NaEtHSO4 was added within 20 min.I allowed this mixture
to distill for a long time before adding the last 20-30 mL. The distillate, water with yellow oil globules present was extracted with ether and the
ether removed by distillation. The residue (12 mL) was saved to be purified further when more nitroethane has been collected.
Experimental 3: The sodium ethylsulfate sol. was prepared as above, except the titrations and sample reactions were not done; the ethylsulfate sol.
made by reacting 600 mL 95% ethyl alcohol and 300 mL 96% H2SO4 was reacted with amounts as above (i.e. 575 g Ca(OH)2, 92 g Na2CO3) and then evaporated
to a manageable amount (125 mL). The NaEtHSO4 solution was reacted with 60 g of NaNO2 in 30 mL of H2O with 10 g of K2CO3 and a squirt of cetyl alcohol
hair conditioner. After the addition 50 mL of water was added. About 400 mL of distillate was collected. The yellow globules of nitroethane were
apparent. This was extracted with ether (2 x 50 mL). The ether removed by distillation and the residue (22 mL) was added to the previously collected
nitroethane.
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FJS
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don't think you done any of these 3 exprience or either you done it wrong!
| Quote: Originally posted by anomolous | | Experimental 1: 300 mL of 96% H2SO4 was carefully added to 600 mL of ~95% ethyl alcohol in a 1000 mL Erlenmeyer. 250 g of anhy. NaSO4 was added and
the mixture placed into the fridge and then into the freezer to cool to about 10C. The hydrated sodium sulfate was filtered leaving ~800 mL of
ethylsulfate/alcohol solution . ..... |
Hope no offense taken but that's my feeling! coz doing chem is not my pro. but always following!  mainly coz I'm doing something relates to solvents.
Anyway regards the EtS initially I considered that very simple but after many (over 5 attempts) find out there's a few trick involved that none told
in initial post or guide. and I do not know why  hope I find time and make it very
simple and stright forward. I mean Ets. not the nitro part. I never done nitro part.
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aliced25
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Water will probably not be promoting hydrolysis of methyl sulfate (see attached paper), but is probably releasing it from the ammonia (I'm not sure of
the reaction between ammonia and sulfamic acid, but I'm guessing there is one). I've also attached the Sartori reference that is often talked about,
with the high-temperature (well -150-160C might seem like high temperature to some) decomposition of methyl hydrogen sulfate to dimethyl sulfate.
Could be useful indeed.
With ammonium methyl sulfate, surely acidification would release the methyl sulfate, which could then be trialed as a source of DMS?
Attachment: Guzowski.etal.Understanding.and.Control.of.Dimethyl.Sulfate.in.a.Manufacturing.Process.Kinetic.Modeling.of.a.Fischer.Est (1.5MB)
This file has been downloaded 1958 times
Attachment: Sartori.MethylSulfuric.DimethylSulfate.pdf (432kB)
This file has been downloaded 1224 times
From a Knight of the Realm: "Animated movies are not just for kids, they're also for adults who do a lot of drugs." Sir Paul McCartney
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Akira990
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I recently googled way to sodium ethyl sulfate. I am posting it here cause i want someone with a bit (a lot) more experience than myself to see if it
is possible or not.
Maybe i shouldnt post it considering last post on this topic was more than a year ago but i will give it a shot and hope someone can explain it to
me..
Procedure.
In 500 ml RB Flask was added 100 ml EtOH (97% is high enough ? ) 96% Sulphuric acid 100 ml (180g) in small portions was added carefully with cooling.
Na2SO4 60 grams were then added and the mixture heated to 120C and kept at that temp for 1 hour. Na2SO4 was filtered off and gave 130 ml of pink
ethylsulphuric acid.
In a 500 ml RB flask in 300 ml EtOH (its essential to use not less alcohol, you'll se why if you wont) were added 66g unhydrous K2CO3. 75 ml of
ethylsulphuric acid were added dropwise with mixing. The ethanol is then distilled off. The wet salt was heated on a plate standing on a water bath
removing the remants of ethanol . Yield approx 85g.
What i do not understand is what for we add K2CO3 in this procedure when we know K2CO3 is insoluble with alcohol.
So i am asking here that someone with experience elaborate this procedure to me (ofc if procedure itself is good)
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Metacelsus
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I've always wanted to try making sodium ethyl sulfate, but I'm worried about forming diethyl sulfate and giving myself cancer. What's the risk of
forming toxic amounts of diethyl sulfate in this procedure (reaction of sulfuric acid, ethanol, and sodium sulfate)?
If it's safe then I will probably try it this weekend.
Also, 120 C seems a bit high in the above procedure. Wouldn't you be making ether at that temperature?
[Edited on 16-9-2014 by Cheddite Cheese]
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Akira990
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If i am not wrong (pls correct me if i am) everything under 140 C is ok and ether wont form...
But my problem is procedure itself cause i am not sure that end product in this procedure is really sodium ethyl sulfate, thats why i asked for
someone with more experience to elaborate procedure...
BTW i can see many answers but they seems to be deleted by admins, pls respond accordingly to forum rules..
[Edited on 17-9-2014 by Akira990]
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Akira990
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After some brainstorming i think i have cracked it.
First part of procedure we have ethanol and sulfuric acid, Na2SO4 is absorbing agent (correct me if i am wrong ) its purpose is to collect any water
left so ethyl hydrogen sulfate not react with water..
Second part of procedure, which also confused me is adding K2CO3 to ethanol. After that we add ethyl hydrogen sulfate (in procedure it is named ethyl
sulfuric acid) dropwise with mixing. My thoughts about this, ethanol in second part is used as solvent and added ethyl hydrogen sulfate will react
with K2CO3 to produce potassium ethyl sulfate (not sodium which we need) and potassium bicarbonate (KHCO3)
I also think there are some problems in this procedure, we use ethanol in second part as solvent but even if it is 97% it still have some water in it
so adding ethyl hydrogen sulfate dropwise might result in hydrolysis instead of reaction with K2CO3 (Na2CO3 for sodium ethyl sulfate instead of
potassium ethyl sulfate)
Last problem is i found some references which says you can do it at 25 C and this procedure says refluxing for 1 hour on 120 C (ethanol, sulfuric acid
and Na2SO4)
Only reason i am posting this here and asking for some kind of help is because i dont want to end up with diethyl sulfate which is toxic. Ofc i can
find myself with few experiments results of each procedure but in case i might end up with deithyl sulfate i would avoid it by any means if possible
[Edited on 18-9-2014 by Akira990]
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Oxirane
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I have made ethyl sulfate many times and attempted to make nitroethane with different methods without confirmed success. My story:
I heated sodium bisulfate and with reflux on and vigorous stirring, added small amounts of ethanol and exothermic reaction took place. Mixing was
essential because hard layer of sodium sulfate formed which prevented the reaction on going. I cracked two glass vessels during my many syntheses
because of this and made one geysir when the formed cake cracked and very exothermic reaction took place between sodium bisulfate and ethanol.
When the reaction was complete, ethanol was added in excess. All solids were crushed and the mixture was filtered and washed with excess ethanol and
then ethanol was distilled off to leave yellow, oily residue. I tried to vacuum this oil, but it decomposed into something that stung my breath very
severly when I later washed off the carbonic residues from the flask. The ethyl sulfate was reacted with sodium bicarbonate to form sodium ethyl
sulfate, which was washed with excess of acetone and dried to form slightly yellow mass.
I attempted to make nitroethane with direct nitrifying with sodium nitrite, and then in another batch which for I made ethyl bromide via sulfuric
acid, ethanol and sodium bromide. From the first reaction I never managed to obtain any residue, but from the later I got about 25ml of oily liquid by
distillation. I dont have equipment to test out what it really was, but boiling range was close to nitroethane. I used continuous flow of CO2 inert
gas for every step just in case because some ppl told NE and side produced ethyl nitrite could cause spontaneous detonations upon contact with air
oxygen.
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Templar
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| Quote: Originally posted by Sedit | | I smell.... I dont care, he writes in a manner acceptable and clear and to me thats all I care about as should you unless you desire to help him.
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Wait isnt sedit a member of various websites dedicated to that certain field of synthesis?
Ethyl nitrite is not explosive last time I checked. Maybe you mean ethyl nitrate?
[Edited on 27-9-2014 by Templar]
He who fights with monsters should be careful lest he thereby become a monster. And if thou gaze long into an abyss, the abyss will also gaze into
thee.
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Akira990
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I have tried sodium bisulfate / ethanol method according to US patent..
I used 138g of sodium bisulfate (mix of powdered bisulfate and larger parts just to check if there is any difference) i made myself... Use powdered
bisulfate, larger parts not good..
46g ethanol, i have used 96%
In US patent i mentioned it is not said how long reflux should last neither it is given any temperature..
I refluxed it for 25 minutes on ~100C.. After that was done i put all in beaker (which is in ice water) cooled it <32C with a lot of stirring...
Than i filtered it few times (more times cause i use coffee filters) with adding ethanol (here it is used as solvent, easier to filter), i was left
with yellow liquid, after that i evaporated ethanol on temperature 90-100 C and final product is ~40 ml ethyl sulfate. At least i hope it is, i am
sure its not ether cause it would evaporate quickly.
I think low yield i have is cause i was too careful with refluxing (was afraid i make ether) and maybe short reflux time..
For first time i am satisfied with the results and next time i will reflux it on little higher temperature for little longer (45 mins probably)
I am going to make 126g of ethyl sulfate (1 mole) only problem is i am not sure which is better for obtaining sodium salt of ethyl sulfate, sodium
carbonate or sodium bicarbonate...
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Metacelsus
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Was the bisulfate anhydrous or the monohydrate?
That yield of ethylsulfuric acid isn't low; it's great compared to anything I've been able to attain. What was the yield of actual sodium ethyl
sulfate?
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Akira990
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I never made sodium ethyl sulfate... I intend to store all ethylsulfuric acid till i get 1 mole (126g) after that i will try to obtain salt form,
sodium ethyl sulfate ( problem is i cant decide which sodium to use, carbonate or bicarbonate, any suggestion)
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Metacelsus
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Use carbonate. Bicarbonate will produce more carbon dioxide (and also water) on neutralization.
Ethylsulfuric acid can decompose in the presence of water, so don't store it for too long.
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S.C. Wack
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90 g. of anhydrous sodium sulfate is placed in a dry 1 L flask connected with a condenser and receiver arranged for vacuum distillation. The flask is
heated by means of an oil-bath kept at a temperature of 155-165°. The apparatus is exhausted as nearly as possible by means of a filter pump [20-45
mm.], and a mixture of 50 g. of alcohol and 104.5 g. of concd. sulfuric acid is allowed to drop through a capillary tube upon the sodium sulfate at a
rate of about 120-150 drops per minute. The distillation of this mixture requires about one and one-half hours for completion. The distillate, which
consists of alcohol and diethyl sulfate in two layers, is separated by means of a funnel. The alcohol thus recovered may be used in subsequent
operations. The diethyl sulfate is washed with a dilute solution of sodium carbonate and then several times with cold water, dried over anhydrous
sodium sulfate and filtered. The product thus obtained is neutral to litmus and analysis proves it to be almost pure diethyl sulfate: yield, 32.6 g.
Other dehydrating agents such as sodium pyrosulfate or anhydrous magnesium sulfate were used but the yield was lower in each case. Increasing or
decreasing the amount of sulfuric acid causes a lower yield. Absolute alcohol does not have any advantage over 95% alcohol nor does fuming sulfuric
acid have any advantage over the ordinary concentrated acid.
JACS 46, 999 (1924)
----------------------------------
4 mol. sulfuric acid was added, with ice bath cooling, to 8 mol. ethanol, over 30 min., keeping temp. under 30C.
Heated to 45C and maintained for 30 min., cooled to room temp., added to addition funnel.
500 ml. water and 291 g. powdered sodium carbonate were mixed, and the addition funnel contents were added with shaking while keeping temp. below 40C
with bath. It's important that the product is neutral to slightly alkaline. Poured into beaker and allowed to crystallize at 0C. Filtered sodium
sulfate which was then washed with 40 ml. icewater.
Filtrate fractionated until the distillate reached 100C, distillate is ethanol. Vacuum distilled residue until 530 ml. remained, d 1.36. Put in
addition funnel.
26.5 g. potassium carbonate was dissolved in 137 ml. water. 320 g. sodium nitrite and 6 ml. castor oil was added. Added condenser and receiver, heated
to 130C with stirring, adding 750 ml. of the above sodium ethylsulfate solution over 1 hour to maintain 125-130C pot temp. Nitroethane started to
distill immediately, and noncondensable gas. Heavy stirring was necessary, sodium sulfate started to crystallize, then foam started to happen at 30
min. 100 ml. water was added over 10 minutes to drive over the last nitroethane.
The entire receiver contents (2 layers) were fractionated. A small amount distilled below 74C and was discarded. Much came over at 87C. Distillation
was stopped with distillate at 100C. Two layers in receiver, lower layer 104 g. nitroethane, ethanol, water; containing 91.6 g nitroethane. Upper
layer 96.1 g., water, ethanol, nitroethane; 4.4 g. nitroethane. Fractionation of lower layer gave pure anhydrous nitroethane.
===========================
Sodium methylsulfate made the same way from 8 mol. methanol and 4 mol. sulfuric acid, with the 30 min. of heating at 50C. 253 g. sodium carbonate was
added to neutralize and make slightly alkaline. Fractionated to 100C as before, but not concentrated in vacuo or otherwise like before. 850-1000 ml.
remained, d 1.3.
Next, same as before but 155 ml. water was mixed with the potassium carbonate, the heating was at 120C, and 150 ml. water was added over 15 min. to
drive over the last nitromethane. Noncondensable gas evolution ended with the end of the sodium methylsulfate addition. Condensable gas gave 20 g.
condensate in a dry ice trap, it was 85% methyl nitrite and 15% nitrous anhydride.
The fractionation of the 2 layers in the receiver gave a distillate to discard, starting between 65 and 79C. 85% of the nitromethane distilled as the
azeotrope at 83.5C. Continued to 100C as before. Receiver lower layer nitromethane, methanol, water, HCN(!!!): 124 g, 118.4 g. nitromethane. Upper
layer same, 68.3 g., 8 g. nitromethane. Fractionated lower layer, 1st fraction 64.5-83C 6 g., 2nd 83-101C (2 layers) 13 g., 3rd 101C, 103 g. pure
nitromethane.
Desseigne and Giral, Cliff's notes
[Edited on 20-10-2014 by S.C. Wack]
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CuReUS
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the success of this reaction depends on the purity and ease of production of ethyl sulphate.Since the ethanol and sulphuric acid method isn't so
good,why can't ethyl sulphate be directly made by passing ethene through conc sulphuric acid.Ethene is sold as ripening gas,so it shouldn't be
difficult to get
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