ideas for breaking down an azeotrope

Distillation methods and improvements.

Moderator: Site Moderator

Post Reply
User avatar
thecroweater
retired
Posts: 6079
Joined: Wed Mar 14, 2012 9:04 am
Location: Central Highlands Vic. Australia

ideas for breaking down an azeotrope

Post by thecroweater »

Haven't had a drink for 24+ hours and I can feel dormant brain cells firing back to life so i thought I'd that this opportunity of this brief regeneration to explore some hypothetical's with those better educated than myself.

If I was to mix my cornice cement (potassium carbonate) with my hydrated lime(calcium hydroxide) using vinegar (acetic acid) will I end up with potassium acetate (potassium salts) from the residue of carbonate acid and hydroxide neutralizing each other. If so can I add the potassium salts to my finished wash, thinking the potassium acetate will significantly reduce the volatility of the ethanol raising its boiling point while not effecting water constituent of the ethanol compound and therefore allowing a separation during distillation resulting in a non azeotropic ethanol (100% ethanol as a separate cut)
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Benjamin Franklin
User avatar
pfshine
Site Donor
Site Donor
Posts: 3106
Joined: Thu Jan 19, 2012 10:59 pm
Location: Vegas

Re: ideas for breaking down an azeotrope

Post by pfshine »

Huh? Its like your speaking english kinda
Life is a journey you take alone. Make sure you do what you what makes you happy
User avatar
Jkhippie
Swill Maker
Posts: 408
Joined: Thu Mar 21, 2013 2:58 pm
Location: Pembroke, NC

Re: ideas for breaking down an azeotrope

Post by Jkhippie »

I don't know the answer, but just so I understand...
Are you suggesting that, added to 96.5% etoh, the K salt would act as a drying agent, thus producing 100% etoh?
The Partridge Family were neither partridges nor a family.

If it walks like a duck, and talks like a duck, there's been a breach in the Duck Containment Facility.
User avatar
thecroweater
retired
Posts: 6079
Joined: Wed Mar 14, 2012 9:04 am
Location: Central Highlands Vic. Australia

Re: ideas for breaking down an azeotrope

Post by thecroweater »

Jkhippie wrote:I don't know the answer, but just so I understand...
Are you suggesting that, added to 96.5% etoh, the K salt would act as a drying agent, thus producing 100% etoh?
To simplify it yes basically. A salt added to any solvent will decrease its volatility meaning it will take a higher temp to evaporate it. So the ethanol it should distil off separately from the water giving you an anhydrous ethanol (about 99.1% ethanol), this will re-hydrate back at azeo (95.63% ethanol) just by being exposed to the atmosphere but you will be controlling almost 100% of what constitutes the 4.37% that is not ethanol hopefully resulting in a pure azeotropic ethanol cheaply and easily, that's the idea anyway
As i understand ethanol boils at 78.2' while water boils at 100' and the azeotrope boils at 78.4' but if you change that boiling point then it should brake the azeotrope distilling off the ethanol separately and yes I was led to believe that potassium acetate does attach itself to the water molecules too to act as a drying agent :thumbup: of course I could be wrong to, its just an idea :wink:
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Benjamin Franklin
manu de hanoi
Site Donor
Site Donor
Posts: 798
Joined: Mon Aug 13, 2007 9:06 am

Re: ideas for breaking down an azeotrope

Post by manu de hanoi »

thinking the potassium acetate will significantly reduce the volatility of the ethanol raising its boiling point
is potassium acetate soluble in ethanol ?
heartcut
Site Donor
Site Donor
Posts: 2781
Joined: Tue Mar 29, 2011 9:31 am
Location: Houston, Texas

Re: ideas for breaking down an azeotrope

Post by heartcut »

Yes, it's used for ethanol precipitation of DNA.
heartcut

We are all here on earth to help others; what on earth the others are here for I don't know.

W. H. Auden
manu de hanoi
Site Donor
Site Donor
Posts: 798
Joined: Mon Aug 13, 2007 9:06 am

Re: ideas for breaking down an azeotrope

Post by manu de hanoi »

it's probably much more soluble in water than etoh if used as drying agent.
Moreover, if we wanted to break the azeo we'd try to bring the boiling points of etoh and water further apart not closer to each other, wouldnt we ?
On top of that the use of the salt would only work for one single evaporation, because being a salt it wouldnt distill.
genejonesiii
Site Donor
Site Donor
Posts: 82
Joined: Thu Oct 25, 2012 7:59 am
Location: Southern US

Re: ideas for breaking down an azeotrope

Post by genejonesiii »

I believe you could add calcium oxide after distillation which will react with the water but it will not react with the ethynol. Then u could filter it and u should have azeotropic solution
User avatar
thecroweater
retired
Posts: 6079
Joined: Wed Mar 14, 2012 9:04 am
Location: Central Highlands Vic. Australia

Re: ideas for breaking down an azeotrope

Post by thecroweater »

I tried that and found it very successful for producing calcium hydroxide for some reason it did not alter the %, maybe it pulled moisture from the air as fast as it took it.
Filtering through dehydrated Epson salts will work better and faster and the salts are recoverable but I am hoping to come across a pre distillation method rather than a drying method
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Benjamin Franklin
genejonesiii
Site Donor
Site Donor
Posts: 82
Joined: Thu Oct 25, 2012 7:59 am
Location: Southern US

Re: ideas for breaking down an azeotrope

Post by genejonesiii »

I am in the process of making a vacuum still I'm hoping with this I can get a purer higher output with these at least that's what my calculation say. I will know by next month hopefully
User avatar
Jkhippie
Swill Maker
Posts: 408
Joined: Thu Mar 21, 2013 2:58 pm
Location: Pembroke, NC

Re: ideas for breaking down an azeotrope

Post by Jkhippie »

thecroweater wrote:I tried that and found it very successful for producing calcium hydroxide for some reason it did not alter the %, maybe it pulled moisture from the air as fast as it took it.
Filtering through dehydrated Epson salts will work better and faster and the salts are recoverable but I am hoping to come across a pre distillation method rather than a drying method
Okay, so.....instead of taking azeo from the still, drying the etoh, rehydrating the etoh with ONLY H2O, you want to take 100% etoh off the still and rehydrate with ONLY H2O, thus saving a step?
The Partridge Family were neither partridges nor a family.

If it walks like a duck, and talks like a duck, there's been a breach in the Duck Containment Facility.
User avatar
thecroweater
retired
Posts: 6079
Joined: Wed Mar 14, 2012 9:04 am
Location: Central Highlands Vic. Australia

Re: ideas for breaking down an azeotrope

Post by thecroweater »

Pretty much :thumbup:
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Benjamin Franklin
User avatar
pope
Site Donor
Site Donor
Posts: 1346
Joined: Thu Feb 02, 2012 3:56 pm
Location: Tinseltown

Re: ideas for breaking down an azeotrope

Post by pope »

This is a very old thread but my brain is all about this topic today - what is the point of going from 96% to 100%? Remove any trace impurities trapped in the water?
"A little learning is a dang'rous thing; Drink deep, or taste not the Pierian spring: There shallow draughts intoxicate the brain, And drinking largely sobers us again." - Alexander Pope
manu de hanoi
Site Donor
Site Donor
Posts: 798
Joined: Mon Aug 13, 2007 9:06 am

Re: ideas for breaking down an azeotrope

Post by manu de hanoi »

pope wrote: Fri Oct 04, 2019 8:27 am This is a very old thread but my brain is all about this topic today - what is the point of going from 96% to 100%? Remove any trace impurities trapped in the water?
fuel ethanol is the point
User avatar
pope
Site Donor
Site Donor
Posts: 1346
Joined: Thu Feb 02, 2012 3:56 pm
Location: Tinseltown

Re: ideas for breaking down an azeotrope

Post by pope »

:thumbup: that snippet of info puts me at ease
"A little learning is a dang'rous thing; Drink deep, or taste not the Pierian spring: There shallow draughts intoxicate the brain, And drinking largely sobers us again." - Alexander Pope
metalsmith
Bootlegger
Posts: 147
Joined: Sat Feb 26, 2011 6:15 pm

Re: ideas for breaking down an azeotrope

Post by metalsmith »

heartcut wrote: Wed Nov 20, 2013 1:30 pm Yes, it's used for ethanol precipitation of DNA.
I had my DNA tested, and it came back I am related to Wild Turkey 101. However I pissed it out before we needed to “precipitate” it. Just my 2 cents....
User avatar
thecroweater
retired
Posts: 6079
Joined: Wed Mar 14, 2012 9:04 am
Location: Central Highlands Vic. Australia

Re: ideas for breaking down an azeotrope

Post by thecroweater »

Extreme zombie thread reanimation alert, I have since learnt one simple way to do this. You can put Epsom salt in an oven or kiln to remove moisture and then use this as a drying agent on azeotropic ethanol to produce anhydrous ethanol but open to the atmosphere it won't stay that way for long. The problem might be that although it is quite soluble in water and can adsorb several times it's own weight it is slightly soluble in ethanol so there is likely to be some contamination.
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Benjamin Franklin
johnnyv
Novice
Posts: 58
Joined: Thu Apr 06, 2017 7:34 pm
Location: Auckland, New Zealand

Re: ideas for breaking down an azeotrope

Post by johnnyv »

You can use a molecular sieve like a 3 angstrom grade of SYLOBEAD, will absorb water but not ethanol and it is a bead so fast and easy to filter compared to a fine powdered sieve like SYLOSIV A3.

After airing off the surface ethanol on the beads you can regenerate in the oven.
User avatar
thecroweater
retired
Posts: 6079
Joined: Wed Mar 14, 2012 9:04 am
Location: Central Highlands Vic. Australia

Re: ideas for breaking down an azeotrope

Post by thecroweater »

I have to wonder what percentage of water does this become a serious issue, I suspect that will vary depending on the various engine tolerances. I remember years ago up in the desert regions it was suggested to add a cup of spirit to your petrol/"gas" tank every now and then. The reason behind this was condensation that forms in storage tanks. Water does not readily mix with petroleum but does with ethanol which will in turn then mix with ethanol and then can be compressed and combusted without risking damage to the motor. It seems to me the higher the water content the higher the risk of damage, that is, above a certain percentage of water it must begin to put a strain on the engine but I have not a clue what that percentage (on average) would be.
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Benjamin Franklin
Post Reply