Methanol concentrate in the tails according an EC study

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Monkeyman88
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Re: Methanol concentrate in the tails according an EC study

Post by Monkeyman88 »

drmiller100 wrote: Fusel oils get run back down into the boiler in both reflux stills and continuous stills. If you had run a still, you could measure the boiler temps. If water boils at 100C, then if you run all the ethanol out of the wash, but the fusel oils are still in the wash, then the boiler will not be boiling at 100C - the fusel oils will cause the remaining wash to boil at some temperature less than 100C. You can use the reflux column to pull off each compound almost separately if you have the patience and a fine enough design.
Actually You will find it boils above 100°c
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Re: Methanol concentrate in the tails according an EC study

Post by Edwin Croissant »

drmiller100 wrote:I thought the sharp smells in the foreshots were mostly methanol, and now I realize they are probably some other compound. I now realize I need to question some of my assumptions, and I am appreciative for that. thank you.
I think that the origin of the myth that all of the methanol ends up in the fores is that people don't now the odor of methanol. It smells a lot like ethanol and that is what it makes it so lethal. There is no way you can detect if the drink you are served is contaminated with methanol. And testing is expensive and requires some very fancy equipment. You can have all the distilling experience in the world but if you do not know how it behaves and if you can't detect it, all that experience is of no use in this case. And that makes most of your post one big pile of fallacies :lol:
drmiller100 wrote:I have been blessed by an expensive education and a mind which understands theory very easily.
Believe me, the result wasn't worth the investment. :lol: And one thing for sure, you are “blessed” with a narcissistic personality disorder :lol:
drmiller100 wrote:On a continuous still, the fusel oils again run down into the boiler, and the boiler will boil at less than the boiling temp of Water.
Wrong, they get trapped in a certain regions in the column and are removed through drawn points on the side of the column.

And this is where you fell through the basket as we say in Dutch, clearly you know nothing about distillation :roll:

Edit: typo
Last edited by Edwin Croissant on Thu Jan 07, 2016 6:50 am, edited 1 time in total.
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Re: Methanol concentrate in the tails according an EC study

Post by Saltbush Bill »

Jimbo wrote: So I will continue to not give a shit about whatever insignificant amount of methanol we're flaming each other over here, and I will continue to talk noobs off the ledge when they come here panties lodged and panicky about methanol in their drink.
+1 :thumbup:
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Re: Methanol concentrate in the tails according an EC study

Post by thecroweater »

Saltbush Bill wrote:
Jimbo wrote: So I will continue to not give a shit about whatever insignificant amount of methanol we're flaming each other over here, and I will continue to talk noobs off the ledge when they come here panties lodged and panicky about methanol in their drink.
+1 :thumbup:
Yup pretty much and as a point of interest the cure for methanol poisoning is ethanol so what little there may or may not be will be countered by the volume of ethanol, unless you are doing something weird, fermenting wood ect it is such a non issue
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Re: Methanol concentrate in the tails according an EC study

Post by Maritimer »

Did you know that you can buy methanol at any hardware store? It is sold as methyl hydrate. Oops,wrong thread.
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

Here a few copy&paste from the pdf:

"The investigation shows that there is in g/hl p.a. an increase of methanol contents during the distillation and especially in the last fractions (tailings). This is caused by the fact that methanol is, in spite of the lower boiling point (64,8°C) compared to ethanol (78,3 °C), carried over in the distillate later than ethanol, an observation that is also confirmed by former investigations and in the literature. This explains the effect that the separation of tailings, which is done for sensorial reasons (2.3), also leads to a reduction of methanol contents of the middlecuts in g/hl p.a. and compared to mash of between 20 and 30 %.

"An extremely late separation of tailing can perhaps cause an increase of methanol contents of about 20 % in the middlecut."

"methanol contents keep a higher value for a longer time than ethanol contents."

"Methanol, specified in ml/100 ml p.a., increases during the donation, while the ratio ethanol : methanol is lowering down. This effect seems to be rather surprising regarding the different boiling points of the two substances: methanol boils at 64,7°C, while ethanol needs 78,3°C. So methanol would be regarded to be carried over earlier than ethanol."

"The main factor that leads to an increase of methanol in the distillates is the recycling of the tailings. Tailings are either add to the next mash to be distilled or collected separately and re-distilled in a separate distillation. Both procedures lead to an increase of methanol contents of between 10 and 20 % gathering all achieved distillates."

"The main reason for high methanol contents (above 1200 mg/100 ml p.a.) is the recycling of tailings, which is practiced in many distilleries, especially in small ones."

"The analysis of the behaviour of methanol during the distillation shows that it is carried over later than ethanol in spite of the lower boiling point. So when the contents of the different fractions are referred to pure alcohol, methanol appears in the highest concentrations in the tailings."

I think, Edwin is 100% right (if we can trust the study).
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

thecroweater wrote:Yup pretty much and as a point of interest the cure for methanol poisoning is ethanol
Yes, I heard of that. It's because the methanol is not the poison, but what our body builds from it (formaldehyde and formic acid). And as long the body has to handle ethanol, the methanol remains unpoisonous.
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Re: Methanol concentrate in the tails according an EC study

Post by drmiller100 »

der wo wrote: I think, Edwin is 100% right (if we can trust the study).
You, personally, have had a reflux still plug with fusel oils? You believe you and EC know more about continuous distillation than me?

You are going to IGNORE the data provided in the study and follow his bullshit conclusions?

You are qualified to decide I have NPD?
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

I looked at the graphs, read the text written about and the conclusions. I think, everything fits together.

I had it sometimes, that I collected 96% (measured by vapor temp), and the stinky last jar watered down to 40-50% were cloudy. Are that fusel oils at the top of my column? I don't know. And I don't know, if it would be an argument.

I am sorry, I'm out here. Of course, many of you can handle with this information better than me, sorry drmiller, I have read your posts here, but I don't see, what you see, I really tried. You are alone here with your opinion. That's ok. That's not the reason for my opinion.

And I don't understand the interpersonal here. I really don't know, why everything is so agressive here now (not only you).
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Re: Methanol concentrate in the tails according an EC study

Post by drmiller100 »

der wo wrote:
And I don't understand the interpersonal here. I really don't know, why everything is so agressive here now (not only you).
Thank you. There was a personal attack on me on this thread. The guy went after me, personally. That annoyed me. I took your previous post as another attack. When I look again, I realize YOU didn't mean to attack me as a person. I pushed back on you pretty hard, and I probably went too far. Sorry.

You don't agree with my opinions, but you show respect for me as a person, and I appreciate that very much.

Again, thank you for taking the high road.

I stated this on another thread, but there is so much crappy information out there it gets frustrating. I read things which are so blatantly incorrect, put forth by people who are experts, but who have never even run a still, yet they have opinions, and they tell me things I have seen with my own eyes are impossible because reasons, it gets frustrating.

Respectfully,
Doug
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

If I look at the first two graphs of the study:

"Dist Nr.4" a stripping run:
Both graphs have 20 mesuarements.
1.mes.: 67% eth. 5250mg/l meth., what means 3134mg/l meth. diluted to drinking strength 40% eth.
2.mes.: 54% eth. 4300mg/l meth., what means 3185
3.mes.: 47% eth. 4000mg/l meth., what means 3404
4.mes.: 42% eth. 3800mg/l meth., what means 3619
20.mes.: 2% eth. 700mg/l meth., what means 14000 (this last calc is a bit theoretical of course)

Conclusion: The ethanol content falls during a stripping run faster than the methanol content. So "in our drink" the methanol content rises the longer we strip. Cutting foreshots out at this run would mean to rise the methanol content.


"Dist Nr.6" a spirit run from low wines (they say "wash" for low wines and "mash" for mash):
2.mes.: 82% eth, 7200mg/l, 3512mg/l meth. dil. to 40% eth.
5.mes.: 82% eth, 6850mg/l, 3341
10.mes: 75% eth, 6200mg/l, 3307
15.mes: 68% eth, 6200mg/l, 3647
18.mes: 60% eth, 6000mg/l, 4000
20.mes: 48% eth, 5600mg/l, 4667
21.mes: 41% eth, 5400mg/l, 5268
27.mes: 5.5% eth, 1700mg/l, 12364

Conclusion: The spirit run acts a little different: The methanol content falls during the fores and the heads. But during the hearts and the tails the methanol content rises like by a stripping run. The rising during the hearts is stronger than the falling in the fores and heads. So at the end we would reduce the methanol content of the drink rather with an early tails cut than a late beginning of the hearts.


Perhaps you can tell me the mistake. Please in easy words.

Edit: Corrected one calculation mistake. Nothing, what would change the conclusions.
Last edited by der wo on Sat Jan 09, 2016 3:06 am, edited 1 time in total.
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Re: Methanol concentrate in the tails according an EC study

Post by drmiller100 »

sigh. I typed this in twice, and it lost it both times. Smiles......

So, this is confusing, and I'd like to understand it also.

I go to the second page 6, about 1/5 of the way down the document. It shows a chart with three elements on it.

Nr. 4 is an alcohol graph.
I go up to page 4, and see what it is. Page 4 shows they started with 5.7 percent alcohol, no plates, no dephleg, no reflux, so a simple pot still.
They ran a pot still on 5.7 percent, and got 68 percent alcohol.

Since you have run a pot still, you know this is horsecrap. 5.7 percent comes out around 80 proof, at first, at best, which is 40 percent. Indeed, I go to

http://homedistiller.org/theory/theory/strong" onclick="window.open(this.href);return false;" rel="nofollow

type in 5.7 percent, and it shows I should get 38.9 percent alcohol.

Therefore, I'm not reading the information correctly, or the report is in error, or I'm not understanding the graphs.
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

They distilled 130l of 5.7vol% without plates and dephlegmator. They collected 30l, almost 25% of the volume. 20 fractions each 1500ml.

In the whole mash is 130 x 0.057 = 7.41l ethanol.
The 1500ml-fractions have: 67, 54, 47, 42, 36, 33, 28, 25, 22, 18, 15, 13, 10, 8, 6, 5, 4, 4, 3, 2%
I calculate from this, that they collected 6.63l pure ethanol, that's almost 90% of the ethanol in the mash. That sounds ok, because the mash had only 5.7%.
All in all it sounds ok in my opinion.

When I run my potstill with 8% mash, it does not start at 48.6% or 94°C as the calculator says, it starts much earlier. But I unfortunately never noted down for example: When I plan to collect 25% of the wash volume, after 10% of the low wines volume I will have ?? abv. The calc is true, but not at the beginning of a run. I think because of the fores and heads and because of the passive reflux of the so far cold lid and riser.

I never ran a 150l still. I think they used an all copper still with a riser for the experiment. We don't know, how fast they distilled (slow increases passive reflux). But it's not unprofessional, that we did not get this information, because it's not a study about distillation speed or ethanol concentration by distillation. We only need this info, when we start to doubt. And I did not those notations, which I mentioned.
So I am not sure, if the graph is too way off the calculator for being real or if it's within the range, what passive reflux and the fores could effect.
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

The only number I have is, when I distill 12l 8% in the boiler, after 10ml of the 3l low wines (I toss the first 10ml always) the temp is around 88°C, what would mean 72%. For 72% distillate strength the calc means, that there are 27% in the boiler...
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

Great thread.

A minor correction, almost off topic but forgive me: fruits and esters ... the fruits they are talking about here are pears which are a member of family rosaceae, which also includes apples, cherries, peaches, apricots, plums, quince, and fruits not fermented such as almonds and rose hip. I would expect this thread to apply to all those fruits. The grape is a different family altogether. The aromatic flavours in muscatel grapes, which make my favourite grappa, I believe are not esters but terpenes and come out at the end of the distillation.
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Re: Methanol concentrate in the tails according an EC study

Post by bilgriss »

There's some interesting content here. Read quickly, it will probably reinforce whatever belief you brought to the table initially. Read carefully, it challenges the same.

One comment I'd like to make regarding the aroma of foreshots and what contribution methanol makes. Another "brewing" venture I've been practicing for a number of years is making biodiesel from waste cooking oil (so there's already a pile of barrels, buckets and drums in the garage...). I also worked for a large volume printer for years which used inks that were primarily diluted with ethanol. For a batch of biodiesel, I work with typically 20 liters of methanol at a time after breaking it down from 55 gallon drums, and have had a sniff from time to time, despite serious precautions. In summary, the two (ethanol and methanol) smell mostly the same, although ethanol strikes me as slightly 'sweeter' and more organic/earthy. More importantly, one inhale of dilute methanol vapors will give you a headache the rest of the day that is truly memorable. Don't replicate my study, please.

In summary, what you smell that stands out in the foreshots is not the methanol, but other high alcohols, which have already been mentioned in detail, and it takes relatively little concentration for those aromas to stand out.
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

Thanks for that comment about smelling methanol, it might come in handy, I have been thinking about an experiment ... which if it happens at my end won't be for a while because I'm unhappy with my column.

It seems to me the core question raised here is whether methanol is pushed into the tails because of its affinity with water, or comes out early because of its boiling point ... or both ... because we need to be wary of false forced choices. Water is the simplest of alcohols, because ethanol has two carbons, methanol one, and water none, so its no wonder methanol and water get on.

So the experiment is: take 10 liters of water, 200ml ethanol, 100ml methanol. Put it in a reflux still and run it on 100% reflux. Measure the head temperature. If we get serious head depression, the early hypothesis wins, and 78C or so, and the water affinity wins. I'm not prepared to argue, but I'll bet the head temp goes down to the methanol BP or close (if the still is any good - more than 3 plates and verified to do that). My bet with anyone who takes it up is that for a nights drinking together, loser provides the whiskey, store bought or home made, winners choice. And when I drink, I drink the whiskey I would like to make, not some JD or JWR crap.

There are lots of obstacles in collecting on that bet, but we need a way of taking a stand without needing asbestos underpants. :-) And I travel a bit, so its not beyond feasibility that collection could be made. When technical disagreement happens, the best resolution is an experiment based on competing hypotheses and a bet.
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

But why 200ml ethanol and 100ml methanol? That's absolutely unrealistic.

Anyway, I don't trust, that pharmaceutical ethanol is foreshots free (I found it has some fruity smell, even the 99.8% stuff). That would affect the temperature and ruin the experiment.

And I don't trust the temperature mesuarement far enough.

I would only trust an EC experiment.
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

I know its unrealistic. Its like the old joke, told by Feynman about the drunk looking for his lost car keys under a lamp-post.
Passer by: "where did you lose them?"
Drunk: "across the street"
Passer by: "so why are you looking here?"
Drunk: "the light is better".

I have access to a still, but it won't detect the levels we are talking about. I've never seen BP depression of more than 1C, though I only recently got a thermometer I trust, and I don't trust the number of plates calculation for my rig (watch this space). We have access to GC data, and we have argued abut how to interpret it.

Ultimately its a question of physics, and how you interpret the graphs and text in that analysis. For the experiment, water is dominant in the starting mix. If the methanol binds to the water, the ethanol will come over first, if the boiling point rules, the methanol will come over first. That is the nub of the debate, the physics, not what is realistic (or at least thats how I read it).

I believe that if you had enough of each impurity in your low wines to fill the column of your still, and you had a column with more than 5 plates, you would see the fractions come off in steps, following the boiling point tables. Am I right? I don't know. I am amazed at how much lactic acid comes over, with a BP of 140C or something. But if we can add impurities to the required level, we can test the theory.

My tag line about measurement was written after beating my head for days against some problem. But its true, measurement is hard, knowing what a measurement means is hard. I'm open to a better suggestion.
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to make whiskey. I think that what we have to say has more lasting value.

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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

Of course such an experiment would be interesting. But after the experiment we will discuss, what the result means in practice. And probably at the end noone will change his opinion regardless of the results.

If we would see a slow rising of the temperature, would it be the methanol coming first because of it's lower BP? Or the ethanol coming first because of it's looser binds to the water?

But a really clear result would convince me. For example, if the column would stabilize at around 65°C, of course it would be the methanol coming first.

But with a LM or VM we could: Stabilizing a column with for example 10%abv ethanol in the boiler. Perhaps do a small fores cut, just for sure. And then adding first a realistic dosage of methanol with a hose through the condenser, perhaps 0.01%abv, and look if the temp changes. And then perhaps higher dosages.

I am amazed at how much peat smoke comes over, with a theoretical BP only.
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Re: Methanol concentrate in the tails according an EC study

Post by Yummyrum »

I've been watching this thread with a mild curiosity. . Firstly I am not a Chemist . I know a reasonable amount about distilling from my around 6 years experience and from what I have read .

My thoughts .
Years ago while trying to understand why Methanol was added to denature ethanol , I read that it was almost impossible to remove it through distillation . At the time I could not believe it possible if they had different boiling points , surely they are separable in a still .Maybe the reality after all is that they can't .

Now seeing Methylated spirit is mostly ethanol , I wonder if the affinity of methanol is to the ethanol and not the water .

Incidentally I do happen to work in a Lab a few days a week and have access to a Heating Mantle , round bottom boiling flask , quick connect glassware with reflux condensers and a cabinet of this to play with .....theres plenty of Methanol . :mrgreen:

I've been thinking same as engunear.
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

I've heard that about separating methanol.

It could be functionally impossible with a pot still. With a pot still, everything smears, and the "things come off in steps" idea is at best a mental model, and worst downright misleading. So if you started with double the lethal concentration, you then get to the lethal concentration, you are just as dead, or maybe you are lucky and just end up blind. And where do you make your cuts if methanol is indistinguishable?

But with a good column and a good thermometer ... on some thread here I plotted a graph that lets you measure how many effective plates your still has. I have not tested my column by this measure as its on the other side of the world to me. But I'm guessing I'm getting 2-3 plates max. So it gets a measurement, then a rebuild, then a test. When I get it over 5 plates then its time to run this expt.

BTW, it all goes down the sink after, followed by a good clean. Whatever the thermo says, this is dangerous shite.
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Re: Methanol concentrate in the tails according an EC study

Post by katzgejm »

fascinating thread. completely turns my understanding of methanol removal upside down!

if i'm understanding this correctly, basically methanol does come off most rapidly in the foreshots/heads, continues to come over in the hearts, and your tails don't have concentrated levels of methanol in relation to total distillate but do have concentrated methanol in relation to ethanol coming over.

so, basically, toss the foreshots and some of the heads, and then don't redistill the tails. yeah?
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

Thats how I read those graphs. Some others read them differently. Not saying they are wrong ... yet.

For heads I agree. They smell awful anyway so thats easy. Tails I don't worry about, but use them in subsequent batches e.g. in the boiler water when steam injecting. So even if there is methanol it gets a chance to get removed. And concentrated tails taste terrible too so they are easy to not drink. (BTW, I'll taste things in small quantities that get spat out followed by a mouth wash.) But if its distilled beer/wine (essentially) and you'd drink the beer/wine, why be concerned about drinking a mix that has less of the heads or tails?

I can't seem to find methanol where I live, so can't yet do that experiment. And attempts to measure the performance of my column have so far failed because its a hard measurement to make for a lot of reasons which I'm slowly trying to sort, so nothing yet to report.
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to make whiskey. I think that what we have to say has more lasting value.

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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

Here is another study, which claims that methanol is more in the tails than the heads:
"Pear Distillates from Pear Juice Concentrate: Effect of Lees in the Aromatic Composition"
https://www.bostonapothecary.com/wp-con ... ntrate.pdf" onclick="window.open(this.href);return false;" rel="nofollow

This study is mainly about the differences between distilling pear brandy on or off the pulp. But it also has interesting results about copper vs glass and about methanol.

About methanol look at the first graph of page 4:
cats.jpg
While the alcohol content of the distillate of a first distillation goes down, the methanol is rising. In the first sample with 700g/l (77%abv) ethanol is 15mg/l methanol, then it rises, the peak is at 45mg/l methanol and 240g/l (29%) ethanol. After the peak the methanol slowly goes down to 35mg/l.
If we would calculate the methanol content in depenence from the ethanol volume and not in dependence of the distillate volume, the graph would look much more extreme.

The comment of the study about this:
In Figure 2A, it can be seen that methanol concentration increased from values around 10-15 mg/L in the first fraction to values around 40-55 mg/L in the middle of the distillation, and then remained constant or slowly decreased until the end of the process. Le´aute´ suggests that because of its low boiling point (65.5 °C), and high solubility in water and ethanol, methanol distills in the head and heart of the distillate only (16). However, studies made by Herna´ndez-Go´mez et al. on melon fruit distillates found methanol in all of the distillation fractions (17). They indicated that this behavior is only to be expected due to the formation of azeotropic mixtures. Apostolopoulou et al. also found methanol in all of the fractions (heads, hearts, and tails) of traditional Greek distillates (18). Finally, Glatthar et al. found the same behavior for pear distillates (11). So, our results are in agreement with these last publications.

It looks, that this surprising behaviour of methanol is proven in three other studies too.
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

Hmmm. Interesting.

Just to check my sanity, I calculated and plotted the partial pressure of the dominant constituents here. It has been observed that some of us don't understand partial pressure and its role, and I would be the first to agree (I have n=1 evidence of this: me, so don't be offended). Boiling points say one thing, but partial pressure means that things come off below their boiling point.

So I plotted the partial pressure using the equations and constants from http://ddbonline.ddbst.com/AntoineCalcu ... ionCGI.exe" onclick="window.open(this.href);return false;" rel="nofollow

The partial pressure magnitude order follows the boiling points. i.e. methanol > ethanol > water. Not really surprising. But it says to me that the expectation that methanol would concentrate in the heads is not just about boiling point. By "concentrate in the heads" I mean if the concentration in the wash is X, the concentration in the heads is > X.

By the way, if any of you are thinking of learning a computer language, try Python. Even if you are not, but use excel regularly for calculations, try it. Its great for this kind of stuff, and once you get over the hump, you will kick yourself every time you open excel out of habit. I've added the code for the graph FYI. Python is free (comes native on macs), incredibly powerful (e.g. used by US Met office for weather predictions), and fun. OK, I'll stop the off-topic plug.
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Partial pressure
Partial pressure
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to make whiskey. I think that what we have to say has more lasting value.

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der wo
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

I don't understand. Do you think the study is wrong? And why?
engunear wrote:By "concentrate in the heads" I mean if the concentration in the wash is X, the concentration in the heads is >X.
But "concentrate in the heads" means normally, that the amount of something is higher in the first jar than in the second jar. And that the dropping is faster than the dropping of the abv. Or in other words it means, that a heads/fores cut reduces the amount in the finished product.
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Re: Methanol concentrate in the tails according an EC study

Post by Pikey »

Hmmm - room for thought here isn't there.

Now, I think I believe the findings that the methanol is pretty much spread out.

Interesting that the reflux and "continuous" stills being argued in some posts as able to separate the alcohols if I'm reading this right.

Then I look at when I used to do a lot of winemaking (Some from fruit and some from other things) and beer making. The real splitting "hangover headaches" used to come from all if abused, but especially a peach wine I made and a potato wine was particularly bad - so much so I would take a LOT of convincing to run anything based on potato !

Then I read posts extolling the virtues of continuous stilling and think of some of the cracking headaches I've had after a heavy night on commercial spirits and beers. I look at my little baby, running in "pot mode" and single running with just 50-100 ml of "fores" discarded and heads / early tails sometimes incorporated and on occasion, with the Heads just imbibed as a drink on their own.

And I'm wondering - If all this is true why do I get splitting headaches on commercial but I don't on my own stuff - Why can I put all the headaches into a "fores" bottle so easily and light the fire with them, when the "Commercials" with their wonderful setups can't do that ?

If I'm not putting methanol into my "headaches" bottle - what am I putting in there ? :?

ANd why don't I get headaches in the morning ?
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der wo
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Re: Methanol concentrate in the tails according an EC study

Post by der wo »

That you cannot concentrate methanol in the foreshots doesn't mean that you cannot concentrate the fores in the foreshots. :lol:
There are many proofs that you can concentrate acetaldehyde and ethyl acetate (the two maior fores components) very effective. For example in this study. Probably they are the cause of the headaches.
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Re: Methanol concentrate in the tails according an EC study

Post by engunear »

Responding to der wo ... no, I don't. I have moved position to "wow thats unexpected", as I was reading the data differently to others. When I see a result that contradicts an expectation then I want double proof, and an experiment with a prior prediction helps a lot. In the new year I may have opportunity to obtain methanol, and then can try a fractional distillation on the three. And if the BP starts above 78 then I'll have 2/2 results.

My dad used to tell me about some people he knew, industrial chemists, who had distilled alcohol in a POW camp. No matter how long they made their fractionating column, they could never got rid of the hangover. The take home lesson for him was that there are mystery compounds that cause hangovers. The lesson for me was that ethanol causes hangovers. And both ideas are probably right. I find there are so many compounding factors for hangovers including how much one drinks, over what timeframe, with what in one's stomach at the start, and even what day of the week it is. For equivalent qty ethanol, I'm sure I suffer worse from Friday night sessions than Saturday, guessing being run down from work has an effect. A bit of a ramble, but I struggle linking hangovers and impurities, except when the controls are really good.
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to make whiskey. I think that what we have to say has more lasting value.

Anyone who tells you measurement is easy is a liar, a fool, or both.
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