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elixirmixer
10-24-2016, 05:32 AM
I read about this in Mark Stavish's "Path of Alchemy" and then, being the consummate delver, read Frater Albertus's "The Alchemical Handbook," Junius Manfred's "Spagyrics" and the two volume set of Jean Dubuis's "Spagyrics." Since then, I have procured all the laboratory glass to pursue the lesser work, including a vacuum pump and vacuum distillation glassware.

By the time I had accrued the vacuum distillation material, I had only about three days left in the waning cycle. I gave it a shot, and collected perhaps 50 mL of a 1000 mL wine at 13.5% ABV. Again, that's some beginner numbers... I waited until this last waning cycle to start and jumped right in...

Again, collected a paltry sum.

Now, here's the rub...

When I tested my collected "menstruum" in a hydrometer tube, seeking the coveted 95.5% or, dare I say, 99.5%, I was dashed. My hydrometer showed that what I had collected, perhaps about 7 or 8 oz, was only at 5% ABV!!! This is after running through about 7500 mL of wine!!

Now, I have to ask, what am I doing wrong with my vacuum distillation? I am heating to 38 C with a constant vacuum of 95 mmHG. I am also running the vacuum the whole time with tube going into the boiling flask that is bubbling the wine and pulling the air through the system into the vacuum. I'm thinking the problem is that the wine is being evaporated at that vacuum. I'm also in New Orleans, and therefore, being below sea level, this may impact the work.

I have since switched to a non-vacuum distillation and I can already taste sharpened difference. With only about a week (and not much more than $50), I might only be able to get 750 mL of a first run, and then will wait the next waxing period to run the entire collection another 6 times, including a Salt of Tartar infusion. I will keep you all posted on this as it develops, but my main drive here in this post is the question about the over water saturated distillation I am pulling.

5% is a very dismal effort indeed. Vacuum pumps are known to take in the vapours of distillates.

A fractional column will improve your 94% to about 97%, The 99.5% only comes through using hydroscopic salts to extract the final moistures. This really is overkill anyway. 95% will strip your taste buds right off and do a very good extraction for the lesser work by any measure.

Also, since you are new, and making your own alcohol, I must warn you, that the first 5% of the distillate should... (no, no...) MUST be discarded, due to it not being ethanol, but instead, methanol, which is an optic nerve poison, capable of doing your eyes and other parts of your body, horrific damage.

Every heard the term "blind drunk?".... lets keep it as a metaphor, shall we...

Spirit of wine, great choice. I would recommend, once you have mastered your distillations, to take all your distillate, pour it back into a full container of distilled water, and distil it again, perhaps a few times, this will clean it of any nasties, reduce any pot-ash remaining and give your spirit the crisp "Triple distilled vodka" taste... and more importantly... reputation ;) :cool:

ghetto alchemist
10-24-2016, 10:05 AM
ElixerMixer is right....your cooling setup is probably inadequate, and you're probably losing
most of your alcohol as vapour, passing it right through the vacuum pump.

You'll need to get a longer condenser and/or use ice water for cooling.

Also you should discard the heads as ElixerMixer said....but don't worry about going blind from methanol poisoning.

My first ever batch of spirits was made from apple pulp.
I accidentally made a brew with a high amount of methanol, and I drank a good amount of the distillate. A few hours after imbibing it, I was left with a dull headache... it only takes a thimbleful of methanol to poison somebody, and I drank several small glasses of it. So why am I not blind? (or even dead)?

Because amazingly the antidote to methanol poisoning, is ethanol (ordinary alcohol).
So as long as your methanol contains some ethanol with it, you'll be fine.

But you should still discard the heads (stuff that comes over at a lower temp), even if just for reasons of purity.

elixirmixer
10-24-2016, 12:38 PM
ElixerMixer is right....your cooling setup is probably inadequate, and you're probably losing
most of your alcohol as vapour, passing it right through the vacuum pump.

You'll need to get a longer condenser and/or use ice water for cooling.


Yes, I should have shared this, Ghetto has shared the solution to your problem.


Because amazingly the antidote to methanol poisoning, is ethanol (ordinary alcohol).
So as long as your methanol contains some ethanol with it, you'll be fine.

Also very true. Only cure, is getting blind drunk!! Nature has a sense of humor ;)

Franklin Fehrman
10-24-2016, 11:59 PM
Thank you both for responding. Firstly, I was not using a fractional condenser, but was using ice cold water. Further, I did assume that I was losing the vapor because my vacuum may be puling too fast and too strong. Now, as soon as the temp was at a little above room temp, I was getting alot of liquid in the receiving flask. And was satisfied my setup was working. Further, with the vacuum, the wine reached a boiling temp right away. I'm going to try a few more distillations where I bring the vacuum from the 95 mmHg up to maybe 300 mmHg, that is, still a vacuum, but, as I live in New Orleans, the average room temperature is already somewhere around 36-40 C. What I mean, is that , if at normal atmospheric pressure, from 78-84 C is the boiling point of alcohol, perhaps it would be better to have a "safe" amount of heat on the Boiling flask, and maybe raise my distilling temperature up to between 50-60 C (as an estimate).

As well, and this regards the second point of collecting the heads, I am of the educated opinion that one collects the heads if one is distilling from a raw mash. What I mean is that, if its sold in a store as wine, or perhaps, 190 proof ethanol (which I'm not using), everything in the bottle is consumable. Everything in a boiling flask that goes into the receiving flask was there in the boiling flask. So, is there methanol present in wine bought from a store? Now, I understand that the process of fermentation, say with yeast, in its basic operation, will have methanol as a byproduct of off-gassing, dead yeasts. Hence, if making a mash from yeast, yes, indeed, recover the heads and tails and throw them away. But if I bought, say, gin, say Gordon's, and distilled it, I wouldn't have to collect the first 5%, I in fact could collect 100% of what I distilled over, as methanol was never present in the original product in the boiling flask. Maybe wine is different somehow. I hope I don't sound argumentative, but I am also aware of the colloquial generality of pitching the heads. My question is, when working with store bought spirits, isn't the methanol already gone?

Franklin Fehrman
10-25-2016, 01:07 AM
This is the setup I'm using.

952

elixirmixer
10-25-2016, 02:17 AM
My question is, when working with store bought spirits, isn't the methanol already gone?

Yes im quite sure that is correct, i think methanol is produced during the fermentation.

Franklin Fehrman
10-25-2016, 03:37 AM
Alright cool. Though, I did run a regular distillation just now over the last three hours, and took out the first 5%. No reason to take any chances. Also, I did a hydrometer test on my collected "first runs" and they collectively came out to approximately 85% ABV. I'm sure that once I finish collecting my first 500 mL of wine spirit, I can do maybe 4 more distillations, and on the fifth, use some salts to sharpen it up, then do two more distillations. I'll let you know how it turns out. I'm also going to contact one of the chemistry teachers at my school and ask them for any advice on vacuum distillation.

ghetto alchemist
10-25-2016, 11:33 AM
you need to stick a thermometer in the vapour, or measure the outside temperature of your stillhead. Use that data for calculating what to keep and what to discard.

elixirmixer
10-25-2016, 12:28 PM
Also, if you wish to master the distillation art, than consider the speed at which you distil. This is another example of where i believe that chemistry simply fails, because no matter the precautions, it is likely that you will continue to have methanol impurities... but the more patience, and the slower the temp increase, the more effectively will you remove that which is more volatile from that which is more fixed.

black
10-25-2016, 01:35 PM
Yes...As Mr Mixer suggests Patience.

'Slowly, slowly catchy monkey'

Learn the Art of Distillation before using
a vacuum pump, it will teach you so much.

Regards.

Franklin Fehrman
10-25-2016, 08:14 PM
So, as a question to all here, as a newbie, how long would it take you all to collect 100 mL of menstruum from wine from, say 1000 mL performing a regular distillation? Just trying to get a ballpark idea here. How many drops a minute/hour should be dripping into the receiving flask?

Franklin Fehrman
10-25-2016, 10:09 PM
954

Lux Natura
10-25-2016, 11:32 PM
This is another example of where i believe that chemistry simply fails, because no matter the precautions, it is likely that you will continue to have methanol impurities...

It seems you have distilled some impurities in your own reply.

Fractional distillation at a rate of 1 drop a second or less is quite common in chemistry as are ultra slow rate vacuum fractional distillation where you are separating things based on less then a fraction of a degree of difference in boiling points. To suggest that a chemist cannot use their equipment to separate fractions is just plain ignorance, especially with methanol and ethanol - as they have a 13C difference in between them! I mean you can do it even without a fractionating column! It really is that easy. Try it sometime.

Most at home distillers have no problem with separating the lighter fractions from the alcohol - and most of them are neither chemists or alchemists, just hobbyists, and in most cases not even using high end glassware and such, but diy setups. The cutting points are quite clear.

This is written from experience.

Try distilling sometime. Your statement that chemists cannot accurately separate methanol from ethanol is pure ignorance.

zoas23
10-26-2016, 12:09 AM
It seems you have distilled some impurities in your own reply.

Fractional distillation at a rate of 1 drop a second or less is quite common in chemistry as are ultra slow rate vacuum fractional distillation where you are separating things based on less then a fraction of a degree of difference in boiling points. To suggest that a chemist cannot use their equipment to separate fractions is just plain ignorance, especially with methanol and ethanol - as they have a 13C difference in between them! I mean you can do it even without a fractionating column! It really is that easy. Try it sometime.

Most at home distillers have no problem with separating the lighter fractions from the alcohol - and most of them are neither chemists or alchemists, just hobbyists, and in most cases not even using high end glassware and such, but diy setups. The cutting points are quite clear.

This is written from experience.

Try distilling sometime. Your statement that chemists cannot accurately separate methanol from ethanol is pure ignorance.

Yes, it can be done with a thermometer... since any distillation of this type with show "plateaus" (I don't know if you use this word in English as to describe the ascending curve of the heat during a distillation of mixed substances and the phases in which the curve gets "flat").

Other than that... going back to the original subject... The authors mentioned in the original post (the first post) for some reason give very BAD descriptions of what happens. I.e, if you try to follow Dubuis in a literal way (and nothing in his texts suggests that he's speaking with metaphors), you'll find very accurate descriptions of some temperatures that you should follow... though when you try it at home... well... his "accurate description" was absolutely inaccurate for me.

Using a vacuum distillation for wine can be OK for learning how to use vacuum pumps... but it's not really the BEST idea if you simply want to extract the ethanol... since the troubles you are having are being caused by the pump and you will probably get better results with a distillation without the pump. I won't judge if the ideas of Dubuis lead somewhere of not, it would be too pretentious from me... but I can say that his "technical descriptions" are quite wrong in many cases and your experience will show you such thing.

Axismundi000
10-26-2016, 12:31 AM
It doesn't really matter how slowly the distillation occurs. Also different equipment will provide varying performance. The issue really is if the drops are too quick it is not good especially if the liquids have a boiling point less the 60centigrade apart, this increases the number of rectifications. With vacuum distillation the two main ussues are bumping and the distillate going upstream to the pump. A claisen adapter and a vacuum reservoir flask will help, better still a stop valve, I'm looking for a good one still, mine is not adequate.

Basic distillation even using aircooled glass like a retort is were to begin. More importantly work with plants not metals initially until you develop proficiency. Plant work with alcohol needs hot plates/mantles, naked flame is just stupid and beginners lab errors with metals you can seriously poison yourself.

So all this how many drops per second stuff is silly excepting it should not run too fast, above 2 drops a second is definately problematic.

As for the methanol thing distilling off the toxic head from alcohol is simple. Say with turboyeast you have 15-20 % alcohol after ferment and you get 3 litres of wine. Fill the 1 litre boiling flask to no more the half and keep all distillate.. Once you have separated all the alcohol from the wine distil the wine spirits you have collected and discard the first 50 ml that you are redistilling. If you don't understand from above go on a wine and beer distilling course or something.

Kiorionis
10-26-2016, 01:44 AM
Once you have separated all the alcohol from the wine distil the wine spirits you have collected and discard the first 50 ml that you are redistilling. If you don't understand from above go on a wine and beer distilling course or something.

And due to the popularity of micro-distillaries (at least here in the US), there are quite a few free websites which go into great detail about heads, hearts and tails of Spirit distillation.

Franklin Fehrman
10-26-2016, 04:32 AM
Thank you, all. That's what I'll continue to do: buy commercially produced wine, distill regularly, toss the first 5%. Then, when I have about 1000 mL of "first run" of 77%, rectify at lower temps, until I have maybe 800 or so mL at 99.5%. Also, ran a distillation this afternoon at 90 C and collected 120 mL of originally 12% ABV from 1000 mL (-5%) and got a first run of about 70%.

zoas23
10-26-2016, 06:02 AM
Thank you, all. That's what I'll continue to do: buy commercially produced wine, distill regularly, toss the first 5%. Then, when I have about 1000 mL of "first run" of 77%, rectify at lower temps, until I have maybe 800 or so mL at 99.5%. Also, ran a distillation this afternoon at 90 C and collected 120 mL of originally 12% ABV from 1000 mL (-5%) and got a first run of about 70%.

The only thing that was not said, but I suggest it, is NOT to discard the first 5% in each of your distillations... but to gather the amount you want and THEN doing a distillation to discard that part, the head. This is because I assume that your flask is something between 2 to 5 liters... and it's safe to discard a "a bit more" (using the thermometer) than what we consider that is safe.... but my experience taught me that if you discard each time when doing several distillations to gather "more etanol", then you will probably discard some ethanol each time... so it is easier to collect your "transparent mix of both alcohols" and THEN discard the part that you do not want.

ALSO, the word "discard" should be discussed... the Methanol is TOXIC, but also useful for other purposes... so I would talk about "separating and keeping it in a correctly labeled bottle" rather than "discarding it", since you CAN use it for several other things (of course, none of them involves consuming it).

Franklin Fehrman
10-31-2016, 10:49 PM
So, by the end of the waning cycle, attained a 95% menstruum. According to Dubuis, this should be enough to start use with a separation. Of course, next waning cycle, I will try to obtain a near perfect menstruum. Reviewing Manfred Junius's illustration of a vacuum set up really helped.