This is very intresting... (oils & alcohol in distilling)

[rad14701]

frosty, what are your plans for that epoxy...???

[frosty]

Thanks Rad,
I was hoping someone would check things over.

I intended to post pictures and a description before continuing. My idea was to use the epoxy in two places. One, to run the condensing line through the bottom of a bucket to use ice water there.
The other was to seal the copper line to the spout end along with the thermometer. I thought to sand the lid lip for a loose fit. I was planning to heat water in a larger container in the microwave and set the copper pot into that water rather than using the hotplate directly.

This is only intended to be used for this experiment and not to be kept as a pot still afterward..

[rad14701]

frosty, if there is ANY chance that someone might actually drink what comes out of that tea pot, do not use that epoxy where hot alcohol vapors might come into contact with it... Using it to seal the worm to the bucket is fine because only cooling water will contact the epoxy...

Personally, even for experimenting I'd skip the tea pot and go with a larger boiler... Anything smaller than ~8 quarts/liters is just too small... I'd consider 6 quarts/liters to be the absolute minimum but would recommend something larger...

[frosty]

Not going to happen..
(drinking anything that comes out of the run that is). This is just for a qualitative assurance that the concept will actually work. Once the idea looks like it will work I'll set about making something to actually optimize the principle, making mods etc. Would have done it today, but the girlfriend had a valve stick in the cooling system of her car and have to work on that.
Thanks for the info about ethanol and epoxy. I was unaware there were safety/health issues there though I would expect it might at least ruin the taste. I will use a torch and proper soldering methods later (being inspired by all the great builds on this site..)

[frosty]

Well this is it..
24 hours and counting. If you think I'm about to kill myself, now is the time to chime in. The epoxy has an hour cure time, but I'm letting it go for 24hrs. I kept a couple of epoxy putty "olives" to put into straight everclear to see if they soften up too much. If so I'll scuttle the tests for now. Otherwise onward I go...
(The collection will not be using the glass shown). There will be a secondary pan as well. There are wooden stir stick spacers between the pan and the pot. The "hot" plate barely boils water with the dial turned all the way up. A fan will be set nearby to add a slight breeze. The paper pad is just there to make the photos easier to see..
The lid pops up straight away if I blow into the end of the worm. If it leaks too much I'll use flour and water..

[rad14701]

Testing the epoxy with Everclear is not a real test... That potential off taste might be poison...

Remember, very few materials, especially synthetics, like epoxy, hose, and tubing, are tolerant of alcohol vapor at 172F/78C, or higher at high proof... We aren't talking about room temperature 150 proof liquid Everclear, or even 180 proof...

And even though that small tea kettle may never put out 190 proof alcohol it will reach temperatures close to 212F/100C at high enough alcohol content to break down most synthetics and leech hazardous chemicals from the epoxy...

Better safe than sorry as far as drinking...

[frosty]

Here are the pictures from the 1st posts. I deleted the posting account just in case..

The test is not a taste test.. I do not plan to taste anything coming out of this. If the spout seal fails, it fails. Then I have to redo the experiment, probably by removing the spout altogether and soldering some sort of connection in its place. But the epoxy is a plug about 3/4 inch thick, so I think it will likely hold long enough to run a couple of tests. I will simulate a "mash" by mixing everclear with water. If I wanted the ethanol to drink I would have done that already..

I know most stills are built with the idea of drinking the output. This is just a test to see if oil suppresses the vaporization of water while allowing the ethanol to vaporize unimpeded.

Are there major physical risks if the seal should fail? That is what concerns me, not whether a toxic substance leaches into the output (which is going to get tossed after it is measured anyways)..

If you feel that is the case, then I'll stop and get a torch. Let me know, thanks.

edit:
The process of using castor oil (if it works as suggested in the Nasa tech brief) may very well introduce some toxic substance into the ethanol in some little known reaction as yet to be discovered. I was not planning to be the guinea pig for the process. I would have the result tested at a lab before considering consumption. It takes more energy to create ethanol than you get back by burning it as a fuel. That would not be the case if an oil layer acts as a catalyst in separation. Granted mixing ethanol with water is exothermic, so some extra energy beyond evaporation of the ethanol would be necessary or the mechanism may be blocked from occurring for some reason not yet understood. That is what I want to find out for myself here.

Maybe this thread would be better placed in the fuel section? Dunno, not my forum..

[rad14701]

While there is only a remote chance of catastrophic failure you have another concern... Leeching from the epoxy could potentially skew your test results... Experimentation needs to be done in a controlled environment and you are adding an unknown variable into your process... Essentially, you are making supposed lab experimentation no more accurate than BevNap chemistry theory... But proceed as you wish as long as you understand the potential problems...

[frosty]

Thanks Rad.. I'll go ahead and give it a test run. I don't believe any amount of leaching will affect the basic observation of whether the output is nearly 95% ethanol or whether it is say only 50/50 which is all I care to see. I just don't want to throw higher amounts of money at something if a cheaper test will negate the need to run a more controlled and also more expensive test.
Had I not observed the castor oil in the little jar expand and then float I would not have bothered to add a little more money to be doing what I am doing now.

I understand the need to hammer home the basics about common dangers (like toxins due to leaching etc) but don't feel the need to scuttle a simple test run if it isn't applicable to my situation. I guess I could just keep quiet and not mention it, but then that bypasses the purpose of using the forum in the first place.

edit:
The primary water in the double boiler pan topped out at 140 F. I was able to get condensation only by removing the double boiler arrangement and putting the pot directly on the hotplate. Cheap Walmart crap.
Current altitude and barometer reading gave me a calculated boiling point for water of 204 F. My cheap thermometer read 200 F while the water boiled out. Half was lost through the lid. I wedged a stick between the handle and lid and replaced the double boiler pan without any water in it.
The temperature gauge looks like things top out now at 190 F but there is no condensate. This is all new to me but probably no surprise to anyone else. So I guess the idea of seeing if I can block the steam with oil is useless since I have to get to boiling before I can get any useful amount of steam.

That leaves simply running the test with the ethanol water mixture with and without the oil to see the results.

If the ethanol/water mixture must boil then the oil layer will be disrupted and the idea will not work that simply. If that is the case then there would need to be multiple stages to the process. First would be to mix the oil with the mash and heat to infuse a concentration of ethanol into the oil. Then the oil ethanol mix would need to be separated from the water/ethanol mix and the ethanol driven off.

How useful this might be will depend on the relative amount of ethanol in the oil compared to the water. That may be the point to which I return.

Here is a pic of a water run of 1 cup. Took an hour to collect.

I'm thinking the whole pot still approach is wrong for this. It has to be driven to function properly. That means boiling temperature for a mixture. I remember some cheap water sanitizing systems used down in New Mexico. Sort of a box of large dimensions but shallow depth with a slanted glass plate roof directing condensation to a side trough which ran to a collection jar. A worm on a pot still is a relatively small condensation area. Works good for a driven system but incredibly slow otherwise. 'Will come up with a new "still" I think.

[frosty]

I mixed 100ml ethanol with 200ml water and another 100ml of ethanol with 200ml of castor oil. Then the oil mixture was added on top of the water mixture.
I set up the camera but the pictures are coming out with horizontal stripes and overexposed looking. I tried new batteries but no luck, so I guess it bit it.
I took the cook pan and filled it with water and heated it up on the hot plate. I put the experiment (in a 4 cup measuring glass) into the pan of hot water.
I set a fan nearby on low to remove the ethanol vapor away from the surface and expedite evaporation. The pan water was 120 F when I first measured it.
After a while, I remeasured the pan water and it had dropped to 115 F, so I cut up pieces of a plastic shopping bag and laid them on top of the water.
After a few minutes the water was at 130 F.

The contents of the measuring cup have reduced from 600ml to 500ml as I type this.
I hope to see it continue to drop to 400ml and then halt.
If there is no more drop after that then I can hope the ethanol has successfully been driven off without any significant amount of water vapor having been driven off with it.
I will then measure the remaining water under the oil and weigh a volume of it comparing it to fresh tap water to see that the specific gravity indicates there is little to no ethanol remaining in the "wash".

I will edit this post with the results.

EDIT (Results):

1st edit:
The water bath topped out at about 145 to 150 F. There are tiny bubbles that form in the water below the oil. These rise to the interface where they collect to rise through the oil layer. They may be ethanol but they may have significant water vapor content as well. Here may be the failure of this concept. What ever water vapor there would normally exist above the water for a given temperature and pressure is blocked by the oil BUT being a vapor it is lighter than both the water and the oil and rises through the oil to escape as it normally would anyway.

So I suspect the original concept is going to prove a failure. There is the possibility remaining of taking advantage of the diffusion of ethanol from the water into the oil which requires no energy input. Then separating the oil from the water and supplying sufficient energy to drive the ethanol out of the oil. I tried this with a blender previous to this experiment and the two layers did separate but the water layer turned white like milk and the oil layer became opaque as well but less so with a tan color. But in theory it should work. No energy wasted evaporating water.

2nd edit:
The oil took over some real-estate at the bottom of the measuring cup. A little later the water rose and took over some of the surface area. When the water broke the surface a strong ethanol smell was evident. So the ethanol diffusion across the boundary between oil and water is not very good apparently. Makes a cool lava lamp though..

3rd edit: After the water broke the surface and released the ethanol it sank again below the oil layer. It still hasn't evaporated down to 400ml yet so I will let it continue to run for awhile to see what happens.

4rth edit: Reached 400ml just after midnight. Letting it continue to see if the water keeps evaporating or not..
WOW shock.. 8 more hours have gone by and the level remained at 400ml while about 90% of the pan water evaporated away! Looks like it does work despite the temporary lava lamp phase, which apparently occurs just to release the ethanol.

5th edit: never assume... yeah evaporation stopped at 400ml but apparently not for the reason I thought to be the case.
I measured the specific gravity of the remaining "water" to be 0.96. (The same as that for castor oil.)
I could smell ethanol in it.
0.96 = x(1.0) + (1-x)(0.79) solving for x gives x=0.81
So the residual water mix is about 81% h20 and 19% ethanol.

So for the "wash" :
ethanol: 38ml left and 62ml driven off
water: 162ml left and 38ml driven off

Vapor driven off was 62% ethanol averaged. (from the water mix - the additional ethanol mixed with the oil at the start is not considered in this. It was added to make sure the oil mixture would float on top of the water mixture)

[blanikdog]

Why do you have ice in the bucket? It isn't necessary and chills the vapour quickly rather that a nice gentle cooling. You really need to do some research.

blanik

[frosty]

Why do you have ice in the bucket? It isn't necessary and chills the vapour quickly rather that a nice gentle cooling. You really need to do some research.

'Wanted to make sure I didn't have vapor escaping out the end. I have not run a pot still before. I am not trying to do anything here that relates to distilling in the normal use of the term. I am attempting to see if there is anything to the idea that oil will allow ethanol to be vaporized while hindering water vaporization.

Maybe in a continuous run reflux still that is not a major energy loss anyhow as the water vapor condenses in the column releasing the energy back to the system.

[manu de hanoi]

so no one pursued this ?

[manu de hanoi]

well i tried and castor oil dissolves very well in 95% but negligibly in 15% so I dont think it would be suitable for recovering ethanol from low abv