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sulfuric acid is the king
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Hmmm so you have done it by acid alcohol methode...
Great.But can you tell me some details...Percentage by mass of the acid,was alcohol anhydrous?How long did reflux take?After reflux you neutralised
acid with water?How much?Please tell me details...I am so obssesed with it i will not stop...It takes me days etc...I have improvised equipment but...
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JJay
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Reflux was 24 hours on a boilng water bath, 200 ml 95% sulfuric acid, 600 ml anhydrous ethanol.
The reflux is probably counterproductive; you might want to just heat it to 70 C for 10 minutes. I am still unsure as to the best neutralization
method.
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sulfuric acid is the king
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Really?Nice then...I must try...
I added calcium carbonate but it was mess...
You have good expirience with buslulfate method?It should work fine...
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JJay
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Adding calcium carbonate is a mess... and you have to stir it to prevent wasting calcium carbonate. I have used the bisulfate method but never got
nearly the yields claimed.
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JJay
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I'm halfway tempted to give this another shot knowing what I know now. I'd like to know the melting point of its anhydrous form (which I assume
exists), and it would be good to know its solubility curve in water by temperature....
I imagine that good results detailing its solubility would be accepted for publication in a respectable journal.
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sulfuric acid is the king
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I found this "With excess sulfuric acid, the equilibrium can
be shifted to the right."
But how much excess?Next time i will try 2:1.
Yes i also need that physical properties,but it's very hard to find anything...
[Edited on 19-2-2017 by sulfuric acid is the king]
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JJay
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I've actually never tried using excess sulfuric acid, but I've seen that recommended in a couple of places.
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sulfuric acid is the king
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Ok,when you have calcium ethyl sulfate,how you add sodium carbonate,in solution or in powder form?
I have improvised equipment and everything,i do not have ph indicators etc,it's very dificult for me,but...
I plan to pour sodium sulfate already in solution to solution of calcium ethyl sulfate,and hope for calcium carbonate forming or "snowing" that can be
only indicator for me,or?
[Edited on 22-2-2017 by sulfuric acid is the king]
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JJay
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That might work well, actually, but I've never tried it.
I have used sodium carbonate and sodium bicarbonate solution, saturated, sometimes adding powder first, and finishing off with saturated sodium
carbonate to a pH of at least 9. The pH seems to decrease slightly when solutions of sodium ethyl sulfate are concentrated over heat unless they are
already acidic... in which case the pH decreases rapidly. Exactly why that happens, I'm not sure, but it seems to be some sort of hydrolysis.
Concentrating the solution under vacuum might keep that from happening. The crystals of impurities obtained while concentrating a solution of sodium
ethyl sulfate, for me, have had different properties... some have been deliquescent, some have had basically neutral pH, some have been sludges that
are hard to filter, some flakes, some crusty substances that creep up the side of the flask, etc. In general, if it remains a solid above 86 C, it's
an impurity and should be removed.
As the solution gets concentrated, any excess calcium salts will slowly precipitate out. Calcium carbonate forms a complex with carbon dioxide that is
actually pretty soluble in water, and there can be a surprisingly large amount of this, especially if you used sodium bicarbonate for the
neutralization. When the solution starts to get very concentrated, unless you somehow magically have absolutely 0 unwanted sodium salts in solution,
the excess sodium salts will precipitate out. When this started happening, you'll want to remove the water slowly--I've usually used a boiling water
bath for this but low heat on a hotplate works ok too--and remove the salts periodically while checking the specific gravity. It will climb very
slowly at times with the elimination of of a lot of salt material, and at other times it will climb very quickly with the elimination of little salt
material. Once you have a saturated solution, the specific gravity will be around 1.33-1.34, and removing water at 100 C won't change the volume of
the solution much or cause precipitation of salts. In fact, it will look like nothing is happening unless you allow the solution to cool, in which
case a crystalline mass of sodium ethyl sulfate will form around the outer parts of the beaker, encasing the solution in a manner reminiscent of
partially frozen ice cubes.
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sulfuric acid is the king
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I use marble as a calcium carbonate source,i hope that's not a problem,i tested it disolving in hydrochloric acid it fully disolved,so it's chloride
now.But i don't know if using crushed marble is good,when i added it to solution of sulfuric acid etc. it formed clumps...Maybe couse i was to fast
adding it.
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JJay
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That probably won't work well... the calcium carbonate needs to be very finely powdered and added slowly with strong stirring so that it doesn't get
coated with nonreactive calcium sulfate. You can use finely powdered chalk if it is actually calcium carbonate. It is also easy to prepare it from
calcium chloride and sodium carbonate.
Edit: Oh, crushed marble. That might work, actually. It needs to be very finely powdered.
[Edited on 22-2-2017 by JJay]
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sulfuric acid is the king
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@JJay
This is from the first try that i mentioned before,solution with misterios ultra soluble salt is evaporated by half and now at 10C crystals!
What do you think?
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JJay
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I would check the specific gravity of the solution to be sure, but it looks like that might be sodium ethyl sulfate.
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sulfuric acid is the king
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Nah...It's to easy... :/
I just touched crystals to get them out,poured remained liquid first,and they are liquidy...Hah...Probably that's just some sulphate monohydrate or
something...
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sulfuric acid is the king
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What i know so far is that it has no pungent smell like sulphate when i made it by h2so4/nacl methode,substance is nearly without smell,and i think
smell is more deep,basic.
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sulfuric acid is the king
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[Edited on 23-2-2017 by sulfuric acid is the king]
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JJay
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That very well could be.
I thought about saving sodium sulfate when it is generated as a side product but so far have always decided it isn't worth it.
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sulfuric acid is the king
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@JJay
Finally i've got some glass.. 
Tell me,after you refluxed acid and alcohol,and made EtHSO4,you poured it to cold water,and then neutralised with CaCO3,or was it directly after
reflux?
Some literature says that first you need to pour it into cold water,then neutralize,but that's nonsense to me,why would you then need high percentage
of alcohol and acid...
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JJay
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I did some more research on it, and it looks like the highest yields are possible by just heating equimolar amounts of ethanol and sulfuric acid to 70
C for 10 minutes without any refluxing. The workup I had most success with was pouring the ethylsulfuric acid into water and neutralizing with calcium
carbonate then neutralizing with sodium carbonate, boiling off most of the water, filtering, and concentrating on a water bath until it freezes when
it cools. I tried neutralizing it directly but then it is a pain to deal with all of the sodium sulfate in its various hydration states, and the
process is not incredibly high yielding unless you use oleum. Someone suggested neutralizing directly and extracting with boiling ethanol. I haven't
tried that and am not sure if ethanol will dissolve hydrated sodium sulfate or not, and most procedures that call for sodium ethyl sulfate expect it
to be in monohydrate form. I'm sure direct neutralization can be gotten to work, though, if you think the calcium carbonate / sodium carbonate route
is too much work.
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sulfuric acid is the king
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Thanks.
Can you explain me why is high yield of both (near anhydrous) needed during the reflux when you later pour it directly to water?
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JJay
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The higher the yield, the less impurities you have to eliminate. The starting materials are cheap.
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sulfuric acid is the king
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I know that but i am confused about water.Why ethanol and sulfuric acid need to be near anhydrous during formation of EtHSO4,but then they can be
simply poured into water?
Why is water undesirable at first step if you put it later,that confuses me.
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JJay
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There is an equilibrium between ethanol + sulfuric acid and ethyl sulfuric acid + water. The reaction that forms ethyl sulfuric acid is reversible,
but hydrolysis is slow. Yet a high concentration of water greatly reduces the rate of formation of ethyl sulfuric acid. A lot of esterification
reactions have similar kinetics (see this one, for example: https://www.youtube.com/watch?v=Ah5ds_3s5BI).
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sulfuric acid is the king
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So once formed EtSO4 can be poured into water without any danger of hydrolysis?
So it's only dangerous during the process of formation?
I think that second step (pouring it into the water) ruins the yield.
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JJay
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I've read that it takes days for ethylsulfuric acid to hydrolyze in water at room temperature. I'm not really sure what the purpose of pouring it in
water is, though.
This paper discusses the effect of water in some detail: https://books.google.com/books?id=zplJAQAAMAAJ&pg=PA456&...
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