Sciencemadness Discussion Board
Not logged in [Login - Register]
Go To Bottom

Printable Version  
 Pages:  1    3
Author: Subject: Nitroethane from ethylsulfate, Desseigne variation.
Antoncho
Harmless
*




Posts: 19
Registered: 22-10-2005
Member Is Offline

Mood: No Mood

thumbup.gif posted on 21-3-2011 at 10:07
Nitroethane from ethylsulfate, Desseigne variation.


The search engine here doesn't show much on the topic of kitchen synthesis of this useful substance, so i'd thought i'd let you know about this recent success of ours at HyperLab.

1. Ethylsulfate preparation (unoptimized).

600 mls 95% EtOH was combined with 300 mls 92% H2SO4. 600 mls of this mixture were slowly dripped into an excess of Ca(OH)2 (amount of lime is determined by titration). Solids were filtered off thru a piece of dense cloth and then filtered clean on Buchner. Filtrations are easy, calcium salts act as celite for themselves.

A sample of thus obtained Ca(EtSO4)2 solution is reacted with an excess Na2CO3, the chalk is filtered and weighed to determine the amount of Na2CO3 needed for neutralization. In this case it was 0.7 mole. The calculated amount of carbonate (made by heating baking soda in the frying pan) solution is added to the reaction and some more carbonate is added until the solution develops an intense blue color on a strip of universal indicator paper (not just bluish tint under the precipitate's spot, intensely blue -- otherwise there's not enough carbonate added yet) .

The solution is again filtered thru cloth and then -- vaccum filtered thru Buchner. Filtering is again not hard at all. Total volume of solution was 1300 mls.

The remaining liquor is placed in a large enameled bowl, on the inner side of which there's drawn a mark of the desired final volume of the liquid. Desseigne's figure is 56% NaEtSO4, density = 1.36 g/cm3, so for 0.7 mole it would bee ~130 mls.

The bowl is put on a electric heater which is turned at FULL THROTTLE (the one in question is 1,8 kilowatt :) ) and a hair dryer is fixed above the bowl so that the stream of hot air is directed at 45 deg. angle to the liquid's surface and towards the open window (unless you want your kitchen to resemble a sauna, that is :P).

This treatment allows one to evaporate ~2 liters of water per hour :o and does not hurt the ethylsulfate a least bit.

When water is removed, the solution is retutrned to RT at filtered from precipiteted salts, mostly carbonate in this case. The authors have gotten 150 mls of solution with sp. gravity of 1.335 g/cm3, which should contain 52% of NaEtSO4, judging by Desseigne's figures.




2. Nitroethane.

A 500 ml 3-necked flask (3 necks is NOT enough for this synthesis, so you'll have to drill two wholes in the central cork: one for the mech. stirrer's faucet, the other -- for the dripper) is equipped with a mechanical dtirrer, an addition funnel, a thermometer protruding to almost the bottom and a straight distillation condenser.

Inside there's placed:

- 32 mls water
- 6.2 g K2CO3 (stirred until dissolution)
- 75 g NaNO2
- 7 g of any hair conditioner (its chief component is cetyl alcohol, serves as a foam killer)

The apparatus is immerged into an oil bath which is also equipped wtih a thermometer. Temperature control is the royal key to success in this synthesis, so both thermometers are mandatory. (The other essential key to success is the quiality of ethylsulfate, but if you do it properly with 'hands growing not out of your ass', as Russian saying goes, you have that already).

The bath temperature is brought to 150-160 C and kept there thru the reaction. The inner temperature, likewise, must bee kept at 120-130 C the whole way.

The NaEtSO4 solution is dripped in during about an hour -- the rate is determined by the speed of distillation / inner temperature. The distillate consists of water and clearly visible driplets of EtNO2 which soon form large yellow globules in the receiveng flask.

When the addition is finished, some water is dropped in to remove the residually remaining product, which presence is easily detected in the distillate visually. In this case 100 mls were needed (in the original procedure that would bee 30 mls, but then again there was obtained a yield better than in the original procedure, so ... :P )

The distillate is chilled well and 100 g CaCl2 is added. The layers separate, the aq. layer is extracted with 50 mls DCM, combined xtracts washed w/brine abd dried overnight with 10 g CaCl2 (for most part of that time the product was kept in the freezer for the fear that EtONO would ruin the EtNO2).

The solution was decanted from the CaCl2 granules into 100 mls RBF, to it there was added a pinch of Zn dust and 200 mg urea. The flask was equipped with a 30 cm column, thermically isolated as well as possible and distillation on an oil bath is commenced. At 50 C bath temp. the mxtr foams heavily, but soon all ethyl nitrite is removed and foaming stops. DCM is then removed slowly and after that heating was brought up to distill off at 108 C 26 mls (51% on NaEtSO4) of clear colorless oil of nitroethane.

A 2 ml sample of this oil was condensed with 2 ml bitter almond essential oil and 0.4 ml MeNH2*AcOH at 70 C for 1 hr. Synchronously there was carried out another condensation -- in all terms identical save for EtNO2 was taken lab grade pure (Acros, 98%+). The yield for both reactions amounted to 1.92 g of nitropropene and was equal to the centimal digit at least (the scale's precision is 10 mg only ;) )


The preparation of NaEtSO4 described here is by no means looked forward to as there is already posted at HyperLab at least two much better yielding reports starting from EtOH and either H2SO4 or sulfamic acid yielding 45% and 80% NaEtSO4 respectively.

The original article by Desseigne and Giral, (which was originally posted on The Hive by Lugh, BTW :cool: :) ) is attached below.





Antoncho

Attachment: EtNO2_desseigne.djv (52kB)
This file has been downloaded 1606 times


[Edited on 22-3-2011 by Antoncho]
View user's profile View All Posts By User
Magic Muzzlet
Hazard to Others
***




Posts: 144
Registered: 22-7-2010
Member Is Offline

Mood: No Mood

[*] posted on 21-3-2011 at 10:59


Great, thanks for this. This seems much better than the route with EtBr/NaNO2, or anything else for that matter.

Thank you for posting it here :)
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1931
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 21-3-2011 at 19:20


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. Unless your willing to imput data that may aid him in his synthesis it should be no concern to you as to his intentions. Other then that its just as simple to say nothing and walk away like when a crackhead ask for spare change and you just roll your eyes and walk away.

Anywho,

Antoncho ... You mention Sulfamic acid, could you please elaborate a bit as well PM me for a direction on a current topic elseware in attempts on Ammonium Ethylsulfate in this synthesis. Also have you considered Simethacone as an antifoming agent as its readily avalible as baby gas drops and more then likely a higher purity then hair conditioner.





Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
mnick12
National Hazard
****




Posts: 404
Registered: 30-12-2009
Location: In the lab w/ Dr. Evil
Member Is Offline

Mood: devious

[*] posted on 21-3-2011 at 19:55


Im not sure if anyone is interested but I will post anyway.

There is some patent floating around here in one of the older threads on producing ethylsulfuric acid from refluxing ethanol and sodium bisulfate,and ethylsulfuric acid can be easily converted to the sodium salt.
I have had mediocre results producing ethylsulfuric acid from sodium bisulfate and ethanol, but both are super cheap and the process is pretty simple. All you do is reflux ethanol and sodium bisulfate until all of it dissolves (never completely dissolves), cool and filter out the sodium sulfate hydrate. What you are left with is a mix of ethanol ethylsulfuric acid and some dissolved salts. Anyway I have found drying and finely powdering the NaHS04 really helps.
View user's profile View All Posts By User
Polverone
Now celebrating 15 years of madness
Thread Split
21-3-2011 at 20:42
Polverone
Now celebrating 15 years of madness
*********




Posts: 3144
Registered: 19-5-2002
Location: The Sunny Pacific Northwest
Member Is Offline

Mood: No Mood

[*] posted on 21-3-2011 at 20:46


Antoncho is welcome here. This is a nice gift of knowledge he brings, and he has already modified the style of his post to match local customs. If you have a problem with this thread please write to me directly rather than commenting in this thread. I have split off the non-technical content.



PGP Key and corresponding e-mail address
View user's profile Visit user's homepage View All Posts By User
Antoncho
Harmless
*




Posts: 19
Registered: 22-10-2005
Member Is Offline

Mood: No Mood

[*] posted on 21-3-2011 at 20:56


1st of all, excuse my using 'SWIM', i haven't realized that this manner of speaking was inappropriate here. I edited my post to exclude all of its occurences in the text.

Quote:
I smell drug cook...


Well i guess after 10 years of being affiliated first with The Hive and later on -- HyperLab.info, it would look ridiculous if i pretended to make nitroethane for rocket fuelling purposes :D:D:D

Still, we at HyperLab are doing what we are doing beecause of scientific interest, not for getting tons of cheap high or - worse yet - monetary profit, as you could've thought.

That's why this synth was performed at all -- its author had a lot of lab grade EtNO2 on hands, but it was not interesting for him to use nitroethane from Acros :)

That's also the reason why the outcome of its reaction with almond oil was immediately after weighing flushed -- honest to goodness -- down the toilet :D The author just needed it to test the obtained EtNO2 on something cheap, otherwise making amphetamine is not interesting for him :)

So please reserve the term 'cook' to some other occasion, we are talking about chemistry here ;)
View user's profile View All Posts By User
Antoncho
Harmless
*




Posts: 19
Registered: 22-10-2005
Member Is Offline

Mood: No Mood

[*] posted on 21-3-2011 at 21:55


Quote:
There is some patent floating around here in one of the older threads on producing ethylsulfuric acid from refluxing ethanol and sodium bisulfate,and ethylsulfuric acid can be easily converted to the sodium salt.


Oh great, you're the first one to have tried this to my knowledge. Did you ever measure the yields?

I'm asking beecause the much talked of way of making HEtSO4 - by dehydration of EtOH+H2SO4 mix with Na2SO4 -- doesn't seem to work as advertised, there have been some cohesive experimentation to prove this. All you get is usually the plain 40-50% conversion (which is obtained without any drying anyways). And much of the Na2SO4 seems to bee converted into busulfate, not vice versa.

Anyway, the best way of making NaEtSO4 is yet to bee reported -- i have no idea why we got so low yield in this case, the other accounts say that if you plainly neutralize EtOH+H2SO4 mix with Na2CO3 you get about 40% conversion. Na2SO4 and Na2CO3 are insoluble in conc. NaEtSO4 solution, so with a careful mode of operation you can get a very clean separation.

Unfortunately, these other reports are nowhere as specific in terms of figures and details as i'd wish from a scientific procedure, so i didn't post them here.

If anyone does it the proper way and reports everything in exact detail, it would be a great piece of knowledge, IMO.

View user's profile View All Posts By User
starman
National Hazard
****




Posts: 318
Registered: 5-7-2008
Location: Western Australia
Member Is Offline

Mood: No Mood

[*] posted on 21-3-2011 at 22:25


I too am interested in what information you can present on the sulfamiic route.No need for 'cloak and dagger' type communication these reagents have many legitimate uses.Post what you have and I'm sure at least a couple here will do some practical experiments.
Thats what we do here ;)




Chemistry- The journey from the end of physics to the beginning of life.(starman)
View user's profile View All Posts By User
Ephoton
National Hazard
****




Posts: 463
Registered: 21-7-2005
Member Is Offline

Mood: trying to figure out why I need a dark room retreat when I live in a forest of wattle.

[*] posted on 22-3-2011 at 00:03


very nice antoncho :)

nice to see you return to your old name as well.

I tried this once but used sodium carbonate rather than potassium.

not the best result.

I do love the way you have not isolated the sulfate.

truly making that stuff anhydrous was a true pain in the ass.




e3500 console login: root
bash-2.05#

View user's profile View All Posts By User
Antoncho
Harmless
*




Posts: 19
Registered: 22-10-2005
Member Is Offline

Mood: No Mood

[*] posted on 22-3-2011 at 01:54


Originally posted by bwz at https://www.hyperlab.info/inv/index.php?act=ST&f=17&...

Quote:


200 g sulfaminic acid pulverized w/a coffee grinder (Note 1) and 300 mls anhydrous EtOH (which was grudged) was refluxed for 3 hrs in a 2 l flask (Note 2). The most part of HSO3NH2 dissolved and a pool of melted NH4EtSO4 is formed on the flask's bottom under the layer of alcohol. EtOH is then removed - first with an aid of slight vacuum, then - at 15 mmHg. The residue of melted NH4EtSO4 crystallized slowly, one has to catch the moment when it gets completely solid, but is still soft. After ir crytallizes fully, it is very hard to recover from the flask. Finally it was obtained 270 g of white crystalline agregates.

295-270=25 g -- EtOH not reacted with sulfamic acid = 52 g unreacted acid
52/270*100=19,3% -- sulfamic acid content in the final product
(270-52)/295*100=73,9% - the yield of ammonium ethyl sulfate.

The product was then neutralized with Na2CO3 and evaporated to sp. gravity of 1,34 g/cm3. It still had a weak smell of ammonia due to the present ammonium sulfamate. After filtering out the crystallized salts the volume of the solution constituted 275 mls.

It was reacted with :

60 mls water
12 g K2CO3
137 g NaNO2
1 mls polymethylsiloxane

...to yield 29 g (34% on NaEtSO4) of clear colorless liquid.


Note 1. It's probably not necessary to pulverize the acid since almost all of it dissolves anyway.

Note 2. The flask should have a bottom surface as large as possible since beecause of the alcohol economy there's a layer of NH4EtSO4 on the bottom that partially retains sulfamic acid. The author had to stir it with a knitting needle occasionally. Using a stirrer would allow to avoid this problem.




So.... As you can see, the most interesting question now is whether it is possible to use regular 95% EtOH in this preparation and how successfully it can bee used. Anyone willing to find that out?
View user's profile View All Posts By User
Antoncho
Harmless
*




Posts: 19
Registered: 22-10-2005
Member Is Offline

Mood: No Mood

[*] posted on 22-3-2011 at 01:57


And oh yeah... Hi guys :hi: , thank you for the warm welcome, i'm glad to see you again as well, old chaps ;)

[Edited on 22-3-2011 by Antoncho]
View user's profile View All Posts By User
mnick12
National Hazard
****




Posts: 404
Registered: 30-12-2009
Location: In the lab w/ Dr. Evil
Member Is Offline

Mood: devious

[*] posted on 22-3-2011 at 13:13


Im sorry I dont remember the yields from the reaction of NaHSO4 with ethanol, but if I remember correctly they were so so. But both the materials are very cheap and can be purchased at any hardware store, thats why this method looked so appealing to me. I am however willing to repeat the experiment and optimize the procedure. This time I will carefully document my results and give a number. But just so you know it might be a while I already have alot stuff going on.
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1931
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 22-3-2011 at 14:16


Thanks Antoncho thats just what I suspected, I wanted to perform the experiment to product Sodium Methylsulfate but never got around to it and now just have yet another Flask of Ammonium Methylsulfate probably going to shit right now. The slight smell of ammonia could be produced from the decomposition of formed Ammonium carbonate which will release NH3 as a decomposition product at a relatively low temperature.




Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
Hexagon
Harmless
*




Posts: 45
Registered: 11-5-2010
Member Is Offline

Mood: Fanf*ckingtastic

[*] posted on 22-3-2011 at 19:10


Just tried that NaHSO4 synth. and all I obtained was an horrible Na2SO4 (?) chunk sticking to the bottom of the flask from witch I could not filter anything... May be next time I'll try to add a large excess of ethanol (used 1 mole NaHSO4 to 1 mole H2O and 0,55 mole of ethanol, water was used because NaHSO4 was anydrous)
View user's profile View All Posts By User
mnick12
National Hazard
****




Posts: 404
Registered: 30-12-2009
Location: In the lab w/ Dr. Evil
Member Is Offline

Mood: devious

[*] posted on 22-3-2011 at 20:15


Yea its a good idea to use a large excess of ethanol, it makes stirring easier, and the end product is much easier to filter. Im wondering how long did you reflux the mixture for? Also im not sure the water is necessary for the reaction and it may be that your "chunk" of solids is a hydrated for of sodium bisulfate. If you do try the reaction again I would recommend not adding water directly to the mix, using a large excess of ethanol, and longer refluxing.

Attachment: US1411215 (1).pdf (173kB)
This file has been downloaded 877 times

http://www.sciencemadness.org/talk/viewthread.php?tid=12034#...

heres the patent I was thinking of and the thread to go with it
View user's profile View All Posts By User
Hexagon
Harmless
*




Posts: 45
Registered: 11-5-2010
Member Is Offline

Mood: Fanf*ckingtastic

[*] posted on 23-3-2011 at 07:16


Quote: Originally posted by mnick12  
Yea its a good idea to use a large excess of ethanol, it makes stirring easier, and the end product is much easier to filter. Im wondering how long did you reflux the mixture for? Also im not sure the water is necessary for the reaction and it may be that your "chunk" of solids is a hydrated for of sodium bisulfate. If you do try the reaction again I would recommend not adding water directly to the mix, using a large excess of ethanol, and longer refluxing.


The mixture was refluxed for something like half an hour, after reading the patent again I think that the cooling process used wasn't convenient too. Yeah next time I'll use a larger excess of ethanol and try to run the rxn anhydrous. I added a mole of water to the bisulfate because it was anhydrous, it's pool grade, tested in a test tube inside a boiling cup of water, didn't melted.

[Edited on 23-3-2011 by Hexagon]
View user's profile View All Posts By User
Hexagon
Harmless
*




Posts: 45
Registered: 11-5-2010
Member Is Offline

Mood: Fanf*ckingtastic

[*] posted on 23-3-2011 at 18:30


Ok, first of all sorry for the double post and if antoncho or another one thinks this is off-topic on this synth. of nitroethane, just let me know.

Did another run with the same ammount of NaHSO4 and an excess of ethanol. The bisulfate is pool grade. The MSDS only lists 100% sodium bisulfate, it's slightly yellowish and comes as very tiny pearls, some of them are clumped but it's easy to break them. Axton brand bought at Leroy Merlin, 2kg for 8€. The ethanol is 96º carrefour brand, lists only 99,9% partialy denatured alcohol and 0,1% benzalkonium chloride, 1,05€ for half a liter.

Added 120 grams of bisulfate (1 mol) to a 600 ml erlenmeyer, then added enough ethanol to cover the bisulfate (75 mls, 0,85 mole) On top of this I put an improvised reflux apparatus made with a big glass funnel and a glass bowl on top with water and ice cubes, at any moment there was ice up there (just changed the ice one time). Yes I know a liebig is superior, but I was too lazy to sep it up :D

So, all this hovering in side of a water bath, stirring with a big magnet. The water was nearly boiling most of the time, and this was left at reflux for an hour. After it, I took it out of the water bath and inmersed it on an ice water bath (with stirring too) for half an hour (until it's cold).

After this I filter the resulting milky solution trough a buchner funnel, with the aid of a fridge pump. Some sulfate ends up at the filtrate and settles to the bottom of the kitasato, so I filter it again trough a coffee filter.

This results on a yellow alcoholic solution weighing 54,2 grams. It gives a red response to litmus paper, with a pH around 1-2 (cant find the colour table right now). Take out of it 10 mililiters with a pipete and weight it, 10,25 grams, so the density of the alcoholic solution is 1,025 g/ml

Taking in account that the density of alcohol is 0,79 g/ml and that of sulfovinic acid (EtHSO4) is of 1,46 g/cm. If it's a solution of only azeotropic ethanol and EtHSO4, the given density corresponds to aproximately a 35% of EtHSO4, or 19g of EtHSO4.

From a mole of bisulfate one can expect max. half a mole of EtHSO4, so that 19 grams are a 30% yield of sulfovinic acid based on sodium bisulfate. In theory one can recover around 45 mililiters of ethanol from that solution.

Any toughts on how this synth. can be optimized? Appart from using a less sloppy technique, may be adding more ethanol since it's so cheap, or increasing the reflux time (or heating, since it looked like it only refluxed at 75% or so...)

The neutralization with sodium carbonate goes for another day, now I've got to clean this mess. Have a nice day :)
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1931
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 23-3-2011 at 19:47


It don't mean much right now but I tossed Some of my Ammonia methylsulfate formed thru the solvalysis of Sulfamic acid in Methanol on to Sodium Carbonate and nothing happened at first. Then slowly it started to fizz like mad meaning indeed the Ammonia methylsulfate was being converted into Sodium Methylsulfate just as I suspected and Antonchos report suggested.

Just a quick an dirty test I know but it gives a good amount of information that would allow easy access to anhydrous Sodium Ethylsulfate thru a simular process.





Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
Chordate
Hazard to Others
***




Posts: 108
Registered: 23-2-2011
Member Is Offline

Mood: No Mood

[*] posted on 23-3-2011 at 22:00


Hmm. I have been wrestling with making nitrobutane by the NaNO<sub>2</sub> method since monday. Three days later i finally have enough pure sample to keep moving on a project, but my yields were pretty atrocious. 3 grams from some 20 grams of starting butyl bromide. Probably my own fault for being somewhat loose with the reaction timing on a number of runs (I was testing a few things. Result: failure). I should try this with a bit of dibutyl sulfide and see if it plays nice. Thankee much antoncho.
View user's profile View All Posts By User
Panache
International Hazard
*****




Posts: 1069
Registered: 18-10-2007
Member Is Offline

Mood: now it seems I’m letting the robots defeat me

[*] posted on 23-3-2011 at 23:50


Some input mentioned another time concerning the use of antifoam.
The trouble usually with antifoams is the tendency for the effect to stop suddenly, this can be somewhat mitigated by being prepared for this eventuality and having further agent ready to dispense immediately into the reaction, also by simply using a small nylon cable tie on the stirrer shaft quite high near the neck. This acts like a small whipper snipper on the encroaching foam and its effect increases with increased stirring rate. Note that this works best when your stirrer and condenser are connected to your flask via a claisen head so that the exiting foam has to get through the stirrer shaft thing.
Beware of using the polyethylene cable ties as they will fail when you really need them at these temperatures.




View user's profile View All Posts By User
atomicfire
Harmless
*




Posts: 37
Registered: 7-2-2011
Member Is Offline

Mood: shaprening my molecular scissors

[*] posted on 24-3-2011 at 05:49


Why do you go though the calcium step? Why not use straight sodium carbonate or sodium hydroxide after mixing the ethanol and sulfuric acid?



ban DHMO
View user's profile View All Posts By User
DJF90
International Hazard
*****




Posts: 2242
Registered: 15-12-2007
Location: At the bench
Member Is Offline

Mood: No Mood

[*] posted on 24-3-2011 at 07:11


Solubility issues. I'll let you read into it yourself...
View user's profile View All Posts By User
atomicfire
Harmless
*




Posts: 37
Registered: 7-2-2011
Member Is Offline

Mood: shaprening my molecular scissors

[*] posted on 24-3-2011 at 08:23


So is the Ca(EtSO4)2 not soluble in water whereas the NaEtSO4 is?



ban DHMO
View user's profile View All Posts By User
DJF90
International Hazard
*****




Posts: 2242
Registered: 15-12-2007
Location: At the bench
Member Is Offline

Mood: No Mood

[*] posted on 24-3-2011 at 09:05


Nope. Both are soluble in water. The reaction mixture is neutralised with CaCO3, the soluble ethylsulfate remains in solution whilst the insoluble calcium sulfate (from the unreacted sulfuric acid) precipitates out. Double decomposition of the resulting solution with Na2CO3 yields the sodium ethylsulfate by precipitation of calcium carbonate. Essentially this workup removes any sulfate from the ethylsulfate, providing a pure product.
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1931
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 26-3-2011 at 20:16


Quote: Originally posted by Antoncho  
Originally posted by bwz at https://www.hyperlab.info/inv/index.php?act=ST&f=17&...

Quote:


200 g sulfaminic acid pulverized w/a coffee grinder (Note 1) and 300 mls anhydrous EtOH (which was grudged) was refluxed for 3 hrs in a 2 l flask (Note 2). The most part of HSO3NH2 dissolved and a pool of melted NH4EtSO4 is formed on the flask's bottom under the layer of alcohol. EtOH is then removed - first with an aid of slight vacuum, then - at 15 mmHg. The residue of melted NH4EtSO4 crystallized slowly, one has to catch the moment when it gets completely solid, but is still soft. After ir crytallizes fully, it is very hard to recover from the flask. Finally it was obtained 270 g of white crystalline agregates.

295-270=25 g -- EtOH not reacted with sulfamic acid = 52 g unreacted acid
52/270*100=19,3% -- sulfamic acid content in the final product
(270-52)/295*100=73,9% - the yield of ammonium ethyl sulfate.

The product was then neutralized with Na2CO3 and evaporated to sp. gravity of 1,34 g/cm3. It still had a weak smell of ammonia due to the present ammonium sulfamate. After filtering out the crystallized salts the volume of the solution constituted 275 mls.

It was reacted with :

60 mls water
12 g K2CO3
137 g NaNO2
1 mls polymethylsiloxane

...to yield 29 g (34% on NaEtSO4) of clear colorless liquid.


Note 1. It's probably not necessary to pulverize the acid since almost all of it dissolves anyway.

Note 2. The flask should have a bottom surface as large as possible since beecause of the alcohol economy there's a layer of NH4EtSO4 on the bottom that partially retains sulfamic acid. The author had to stir it with a knitting needle occasionally. Using a stirrer would allow to avoid this problem.




So.... As you can see, the most interesting question now is whether it is possible to use regular 95% EtOH in this preparation and how successfully it can bee used. Anyone willing to find that out?


There are a couple things that bug me about this synthesis of Ammonium Ethyl Sulfate.

First off he used a little over 2 mols of Sulfamic acid where as he used a little less then 10 mols of EtOH yet he reports that some Sulfamic acid remained after the reflux.

This is just not so. This is a Solvolysis reaction. As the reactant is taken up into solution that is when it reacts to form the desired product. What he had in the bottom of the flask left over was unreacted Sulfamic acid... NOT Ammonium Ethylsulfate.

When forming the Methyl variation I have noted that it only takes around a 3-1 molar ratio at most EtOH to Sulfamic acid to ensure that SIX hours into it there will be nothing more then a slightly yellow solution remaining and no solids at all. With stirring the solvolysis can be accomplished in under 3-4 hours with only a 2-1 ratio and a clear colorless solution is obtained which will precipitate long clear needles on cooling when 1/3 of the solution is distilled.



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.





Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
 Pages:  1    3

  Go To Top