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ideas for breaking down an azeotrope
Posted: Tue Nov 19, 2013 6:22 pm
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)
Re: ideas for breaking down an azeotrope
Posted: Tue Nov 19, 2013 6:27 pm
by pfshine
Huh? Its like your speaking english kinda
Re: ideas for breaking down an azeotrope
Posted: Tue Nov 19, 2013 6:44 pm
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?
Re: ideas for breaking down an azeotrope
Posted: Tue Nov 19, 2013 7:33 pm
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
of course I could be wrong to, its just an idea
Re: ideas for breaking down an azeotrope
Posted: Wed Nov 20, 2013 10:31 am
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 ?
Re: ideas for breaking down an azeotrope
Posted: Wed Nov 20, 2013 1:30 pm
by heartcut
Yes, it's used for ethanol precipitation of DNA.
Re: ideas for breaking down an azeotrope
Posted: Wed Nov 20, 2013 10:22 pm
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.
Re: ideas for breaking down an azeotrope
Posted: Thu Nov 21, 2013 5:06 pm
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
Re: ideas for breaking down an azeotrope
Posted: Thu Nov 21, 2013 5:15 pm
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
Re: ideas for breaking down an azeotrope
Posted: Fri Nov 22, 2013 9:17 am
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
Re: ideas for breaking down an azeotrope
Posted: Fri Nov 22, 2013 10:39 am
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?
Re: ideas for breaking down an azeotrope
Posted: Fri Nov 22, 2013 5:19 pm
by thecroweater
Pretty much
Re: ideas for breaking down an azeotrope
Posted: Fri Oct 04, 2019 8:27 am
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?
Re: ideas for breaking down an azeotrope
Posted: Fri Oct 04, 2019 8:34 am
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
Re: ideas for breaking down an azeotrope
Posted: Fri Oct 04, 2019 8:47 am
by pope
that snippet of info puts me at ease
Re: ideas for breaking down an azeotrope
Posted: Fri Oct 04, 2019 3:45 pm
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....
Re: ideas for breaking down an azeotrope
Posted: Sat Oct 05, 2019 8:32 am
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.
Re: ideas for breaking down an azeotrope
Posted: Tue Dec 03, 2019 2:07 pm
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.
Re: ideas for breaking down an azeotrope
Posted: Wed Dec 04, 2019 1:02 am
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.