Chemistry help (Manganese Dioxide)

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Chemistry help (Manganese Dioxide)

Postby Pervak » Tue Sep 09, 2008 8:26 pm

I've bin told a Russian moonshiners trick is to add small amounts of Manganese dioxide to the low wines. It supposedly decreases the smell (I'm assuming the smell of tails).
Some googling showed that it's an oxidizer.
"Allylic and benzylic alcohols can be oxidized in presence of other alcohols using certain selective oxidants such as manganese dioxide (MnO2)." ( http://en.wikipedia.org/wiki/Alcohols#Oxidation )
It's also used to make rum smell (viewtopic.php?f=3&t=4839&p=6723744)
I added a small amount to low wines, it dissolved turning them first pink then brown, in a day it completely precipitated on the bottom leaving low wines crystal clear.
Can someone explain what adding an oxidizer (Manganese dioxide) to low wines will do?
I haven't drink them, but my buddy (who also runs a still) carbon filtered those low wines and drinked them without apparent ill effects.
Any thoughts on this would be greatly appreciated.
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Re: Chemistry help (Manganese Dioxide)

Postby muckanic » Wed Sep 10, 2008 7:27 pm

Adding an oxidiser is a bit like fast-tracked barrel ageing. The main thing a mild oxidiser like MnO2 will do is convert alcohols to aldehydes, which often have a fruity note (think sherry). I would have thought that would increase the odour, if anything. MnO2 generally won't convert alcohols into carboxylic acids, so the suggestion in the rum link that it could facilitate ester formation could be a little off. The final precipitate is MnO, which presumably has some non-negligible solubility in water (which is why you would want to re-distill).

There is a bit of lab technique usually involved with any oxidation. Namely, you don't just dump the whole oxidant quotient in at once. Instead, you normally drip it in, with stirring and temperature control. Another consideration is pH control, as many oxidants consume either acid or base (although MnO2 appears not to - I don't have redox reactions at my fingertips). I am also a little hazy as to why the oxidant might prefer to react with higher alcohols rather than with EtOH. Presumably, if you use too much of it, you will wind up with acetaldehyde, which isn't desirable in large amounts.
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Re: Chemistry help (Manganese Dioxide)

Postby seravitae » Fri Sep 12, 2008 10:43 pm

manganese dioxide does act as an oxidant, but generally this is only with a special form of manganese dioxide, called 'activated manganese dioxide' and is so because of other chemical washes (boiled in 37% hydrochloric acid) and usually after precipitation from a soluble manganese salt as to create very fine nanoparticles with high surface area. It will certainly not be food grade. Also, MnO2 is a very fine black powder (think of laser jet toner), and insoluble in water, so you will have a LONG LONG time spent cleaning it out of stuff. Trust me, we use bags of it at my old lab, and we distill our product from it - it even comes over in the vapour and crystallises all up the condensor making it a royal pain in the arse to clean and seperate.


I would really think that unless you REALLY know what you are doing and can chemically confirm the quality of your MnO2, and it's source, plus have a lot of good lab-grade equipment that you should stay away from this idea for safety reasons...
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Re: Chemistry help (Manganese Dioxide)

Postby manu de hanoi » Sat Oct 25, 2008 9:54 pm

From Andre.silent :
Several hints how to make it easier and more efficient (note: only applicable when you go for neutral spirit).
1. Treat your raw spirit with small amount of NaOH. The goal is to decompose the ethyl acetate into ethanol and sodium acetate (also other esters). The amount should be realy small (as small is the content of ethyl acetate). It is better to put less than too much - you should make some experiments to establish the correct value.
2. After that you should add few drops of the KMnO4 solution (purple crystals). This is the strong oxidant transforming aldehydes into acids. It is so strong that it could oxidize even ethanol into acetic acid - this however is avoided due to high pH of the solution after addition of NaOH.
3. The reaction is rather fast so after couple of minutes you can see the precipitation of black and brown flakes of MnO2 - this is the end.
4. Filter the raw spirit and off you go with the batch distillation.
5. Please notice that the best result of the rectiffication you get only when the feed is the high strenght alcohol. Only then you get sharp division between different fractions. Water makes them more diffused.

I PM him for details on KMnO4 but after 4 posts he vanished from the forum
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Re: Chemistry help (Manganese Dioxide)

Postby HookLine » Sat Oct 25, 2008 11:35 pm

KMnO4 is potassium permanganate.

http://en.wikipedia.org/wiki/Potassium_permanganate

Be careful when mixing it with strong acids.
Be safe.
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Re: Chemistry help (Manganese Dioxide)

Postby muckanic » Sun Oct 26, 2008 4:31 pm

From Andre.silent wrote:2. After that you should add few drops of the KMnO4 solution (purple crystals). This is the strong oxidant transforming aldehydes into acids. It is so strong that it could oxidize even ethanol into acetic acid - this however is avoided due to high pH of the solution after addition of NaOH.


So what is the point? This creates a bunch of non-volatile carboxylate salts. If someone wants to try making esters thermally in the still, then it would require acidic and preferably near anhydrous conditions. Except that step #1 is designed to decompose esters! If someone wants volatile acidity for some strange reason (and assuming it gets past any basic copper patina), then that also requires acidic conditions.
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Re: Chemistry help (Manganese Dioxide)

Postby manu de hanoi » Sun Oct 26, 2008 10:01 pm

muckanic wrote:So what is the point?

To remove aldehydes
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Re: Chemistry help (Manganese Dioxide)

Postby muckanic » Mon Oct 27, 2008 3:53 pm

There remain the questions of:

1. why permanganate would preferentially oxidise aldehydes rather than alcohols.
2. even if so, what happens if a slight excess is added. In other words, how to get the quantities exactly right.
3. whether there would be any secondary reactions from the MnO2 created in the permanganate reaction.
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Re: Chemistry help (Manganese Dioxide)

Postby seravitae » Tue Oct 28, 2008 11:05 pm

permanganate doesnt preferentially oxidise, it oxidises the crap out of anything (in acidic conditions)

ive said it before and ill say it again, unless you can get food grade manganese dioxide, forget it.

also, as said before, you can't just use any old manganese dioxide because it hasn't been activated...

this is a pointless excersize
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Re: Chemistry help (Manganese Dioxide)

Postby dixiedrifter » Thu Oct 30, 2008 1:01 am

Hmmmmm might be possible to take manganese sulfate, hit it with sodium hydroxide and hypochlorite similar to the method used to make nickel peroxide...

But then again, it would be very very messy stuff to have to deal with.
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Re: Chemistry help (Manganese Dioxide)

Postby seravitae » Sat Nov 01, 2008 2:07 am

guys you are really dancing with the devil here...

you do not have the analytical skills to prove what you have made is safe for human consumption.. do you really want to mix your alcohol with drain cleaner and bleach? (literally!)

this thread should be locked for human safety reasons. someone's going to get hurt if they attempt this. residual hypochlorite is reactive with ethanol and will lead to toxic products being formed.

the original poster said this was an old 'russian moonshiners trick'. I needn't remind anyone how many people have been killed by russian moonshine because of how poor quality it is, often containing antisceptics, pesticides and other garbage.

if you're having problems with the purity or quality of your distillate, you need to ferment, distill or polish more carefully, or use better equipment. not mix it with chemicals of random purity from dodgy factories in china.

ps not to stroke my ego but i have a degree in medicinal chemistry, and i would never feed this to anyone, even if it met human consumption standards. just on prinicpal alone
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Re: Chemistry help (Manganese Dioxide)

Postby rad14701 » Sat Nov 01, 2008 6:37 am

seravitae, I am in total agreement that the moderators need to start buckling down on bad and dangerous advice being given... Some threads should be removed, not simply locked... Threads which show a disregard for health, safety, or ethics, have no place in a forum that is considered by many to be "the" premier source for honest and accurate information for the home distiller... At the very least, a bold message stating that the forum moderators don't condone the advice being given should be added in questionable threads... Not that I want to dump additional work onto the staff, but I think it's needed...

I must be in Saturday morning rant mode... :roll:
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Re: Chemistry help (Manganese Dioxide)

Postby theholymackerel » Sat Nov 01, 2008 6:41 am

On one hand ya make a good point, on the other hand the average poster here explodes into into a furious ball of explicitives at ANY HINT of cencorship, as my Private Message folder can attest to...
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Re: Chemistry help (Manganese Dioxide)

Postby rad14701 » Sat Nov 01, 2008 6:56 am

theholymackerel wrote:On one hand ya make a good point, on the other hand the average poster here explodes into into a furious ball of explicitives at ANY HINT of cencorship, as my Private Message folder can attest to...

I hear you... I run a forum and over there it's my way or the highway... Moderator staff decisions are not up for debate... Most complainers don't know what they're talking about anyway so their complaints are a moot point... <<< not to be read that my complaint/concern/opinion should be considered a moot point >>>
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Re: Chemistry help (Manganese Dioxide)

Postby theholymackerel » Sat Nov 01, 2008 7:05 am

A few University Chem classes don't qualify me to comment on this thread in a technical way. I will say that I think fine handcrafted booze can be made without ANY chems. I also think it's a bad idea to emulate Russian bootleggers.

My personal policy is to let folks talk about whatever they want and only step on someone hard when they explode on someone and act the ass. So I'll let this thread continue as long as everyone's polite and plays nice. I can't say what the other mods will do.
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Re: Chemistry help (Manganese Dioxide)

Postby manu de hanoi » Sat Nov 01, 2008 7:11 am

rad14701 wrote:seravitae, I am in total agreement that the moderators need to start buckling down on bad and dangerous advice being given... Some threads should be removed, not simply locked...


My guess is most factory use chemicals at least to adjust pH, they just dont advertise it. Sulfuric acid and lime were used extensively 150 years ago for that purpose (and since then I guess). Now about the KMnO4 and such, nobody here said it was safe and opinions on the dangers involved are welcomed, that's also why it was posted here in the first place, just be reminded that if that thread had been deleted, you could not even have expressed that opinion. Are you sure it would have been better ?

I forgot which moderator said that this forum should not be "dumbed down" (when talking on unifying measurement units and publishing a to z how tos), censorship is dumbing down the site. The "research" section of the forum is a research section. Put a disclaimer if you like.
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Re: Chemistry help (Manganese Dioxide)

Postby seravitae » Sun Nov 02, 2008 3:51 am

Yes, most factories do use chemicals. In fact the ethanol industry *is* a chemical industry (and a chemical itself)..

My point of commenting here is certainly not to voice an opinion, and id rather this thread not exist becuase so far it's gone from telling people to add MnO2, to a post on manufacturing synthetic chemicals using bleach and other nasties designed for human consumption...

a plain fact - home brewers simply don't have the same facilities or stringent quality control and analytical systems that a distillery does. in the real world you can do whatever you want, and i wont stop you *or* tell you what to do.

Im simply putting it out there that I don't believe you have food-grade QA staff and analytical facilities to even be sure:

a) how pure your MnO2 is and if it meets any health standards

b) what TYPE of MnO2 you have (because your beloved post about using MnO2 to oxidise things does NOT work unless you use special conditions and a special type of MnO2.MnO2 needs to be extremely finely precipitated, washed under highly acidic conditions and nearly pyrolysed to become "useful" like you suggest. MnO2 off the shelf won't do shit - it's used as a pigment (black paint) because of its color, and NON reactivity. you would need extensive equipment to model the surface of your MnO2 to see what form it is in and thus its reactivity and usefulness.

c) removal of your byproduct. after using activated mno2 in the lab and it forming a complex with something else in solution, some byproduct in water, we found that the complex would spontaneously "distill" itself along with our product - even though it was a solid! it would sublime up the rotovap unit invisibly and we found large quantities remaining in the product, dispite what chemistry tells us about MnO2 and other inorganic solids and distillation theory!

censorship is not dumbing down this site. if that were true people would be wailing about the whole "plastics in stills" philosophy instead we use common sense about our lack of knowledge on the subject and deem it unsafe. here the same applys. you frankly don't know what you're doing, how the chemistry works and are relying on information from widely known dodgy sources.

again censorship doesnt dumb down this site or any site. dumb people dumb down sites - idiocy doesnt come from any other source. if you want to win the Darwin award, be my guest.. i wont be posting anymore in this thread, because i dont want to be at all responsible for any innocent uneducated kids out there reading this thread and thinking they can clean up their crap product by dumping hardware-store grade pool chemicals/pigment/whatever into his batch and feeding it to people.

another aspect of people's idiocies is not listening to people who can provide useful knowledge. theres a reason why we censor people talking about plastic in stills - its because the old timers and experienced ones with the skills (like the chemist) have real knowledge in this area and have shown it to be unsafe. unless you have the skills to prove otherwise, this is a very good oppertunity for those more experienced than you to say "Because I said so".

in a nutshell, i have nothing against MnO2 being used to remove traces in alcohol. i do however have a problem with *you* doing it, since you've demonstrated that you haven't seriously considered the impacts enough.
over n out
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Re: Chemistry help (Manganese Dioxide)

Postby manu de hanoi » Sun Nov 02, 2008 9:39 am

Hi Seravitae,

When I said the industry has been using chemicals for more than a century I didnt mean to advocate for the synthesis of MnO2. I just wanted to emphasize that we shouldnt be shy talking chemicals.

Your point about Mno2 was clear already , but thanks for the new details. Thanks also for the warning about chemicals purity that is very important and I support that.

About "the young kids being poisoned because they read the thread" argument, please be reminded that everyone was very cautious in that thread and no one posting in this thread claimed anything worked or was safe. Andre a retired poster said that KMnO4 would work in basic conditions. you didnt read carefully and jumped on it saying it wouldn't in acid conditions....I believe the whole idea of the oxydizer (h202, a bleaching agent, should be discussed too) is interesting and we should keep on talking about it despite our limited knowledge.
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Re: Chemistry help (Manganese Dioxide)

Postby dixiedrifter » Sun Nov 02, 2008 5:23 pm

Well let me finish this thread...

Manganese is a neurotoxin and it is possible to get manganese poisoning. It is not necessarily all black, some of the pottery grade is brown. Manganese that comes in pottery grade is finer than powdered sugar and is a MESS to clean up.

Manganese exists in numerous oxidation states, Mn02 is just one, and it is sufficiant to oxidize some of the the alcohol to an aldehyde. Washing manganese dioxide with concentrated hydrochloric acid will result in chlorine gas being produced and with concentrated sulfuric acid the pink sulfate will form.

Personally I would never ever recommend putting Mn02 or or KMn04 in a still due to it being such a pain to clean up.
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Re: Chemistry help (Manganese Dioxide)

Postby HookLine » Sun Nov 02, 2008 7:20 pm

dixiedrifter wrote:Manganese is a neurotoxin and it is possible to get manganese poisoning.


Yes, and no. Manganese is a necessary trace element for all organisms. As with many nutrients, the dose determines the poison. Too little, or too much, and you suffer.
Be safe.
Be discreet.
And have fun.
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Re: Chemistry help (Manganese Dioxide)

Postby manu de hanoi » Mon Nov 03, 2008 4:04 am

dixiedrifter wrote:Personally I would never ever recommend putting Mn02 or or KMn04 in a still due to it being such a pain to clean up.

I think the idea is to pour the KMnO4 drop by drop, when the violet color seems to persist longer than usual slow down or stop the drip.
After an hour the MnO2 falls down to the bottom, so you can separate it. In order to compare the purities of alcohols
I did some tests with KMnO4 by measuring the time it took for several alcohols to react and remove the purple color, and indeed tails & 1st pass distillates would bleach much faster than the final product.
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Re: Chemistry help (Manganese Dioxide)

Postby andre.silent » Thu Nov 06, 2008 3:24 am

Hi everyone,

First of all I apologize for vanishing form the forum.
Unfortunately I had no time nor opportunity to restart my distillation activities. So I may say I am more than retired poster - I am retired moonshiner.
The forum is so excellent that some time ago I found my knowledge and experience not strong any more to act as a "proffesor" - I decided to learn instead.
However I am still a thinking person and probably I can add some common sence remarks (together with some chemistry information).

First of all I believe that people who do the distillation are thinking people (otherwise they would drunk themselves to death) and they use a common sense as a very powerfool tool to survive.

Here we go:

1. Chemistry is nothing wrong by itself - we all use chemistry almost every day - especially in the kitchen. When you do something wrong there, nothing happens except stomach ache or in worst case vomiting - then you dont do it again. When you drink your booze and the next day you cannot turn your head without horrible pain - you don't do it again (do you?). At least you start to think what have I done wrong - and try to improve it or avoid it. This is a common sense. Usually it doesn't kill you - unless you drink pure methyl alcohol.

2. When you make a mash - this is really a big chemistry. You end up with product which contains almost a hundred of different byproducts. They exist there even after carefull distillation. Actually some of them should be there to give you a scent of rum, cognac or whiskey.
3. Please take in mind that you also use a chemistry during the distillation. Have you ever thought why copper is the most common material for distillation equipment - one of the reasons is that copper comes into reaction with sulphur containing components (protein related byproducts present in a mash). This way you impove your product to the great extent (stainless steel wouldn't do it).
Chemistry? Yes. Could it make you harm? Yes. But only if you do some crazy moves towards ammonia formation - then you may end up with blue distillate - containing harmfull copper compouunds. Should you resign from using copper stills? No!

4. When you do the distillation - you cannot avoid the esterification reaction going on (the reaction between acids and alcohols which both exist in your mash). However in very diluted mash the conditions for this reaction are not very favorable. This is little bit more important when you do the low wines distillation as you have higher concentrations of reagents. Please take in mind that esteriffication not only gives you more forshots but also "consumes" ethanol. This is the reason why you should do something just before the second distillation.
5. The way to do it is to add some NaOH and some KMnO4 to you raw alcohol. The chemistry is as follows:
a) Addtion of NaOH in a first step binds acids into salts which are not volatile (here is the example of acetic acid, but it works for any others as well)
CH3COOH + NaOH = CH3COONa + H2O
(acid) (salt)
b) Some more NaOH decomposes esters (moves the reaction equilibrium back to alcohol and acids - which are bound into salts again). The example shows the reaction of ethyl acetate which is the most common ester in a mash.
CH3COOC2H5 + NaOH = CH3COONa + C2H5OH
(ester) (salt) (alcohol)
c) The purpose of KMnO4 addition is to oxidize aldehydes into acids (which are again bound by NaOH into salts). Believe me aldehydes are far nastier then esters.
2KMnO4 + 3CH3CHO + NaOH = 2CH3COOK + CH3COONa + 2MnO2 + 2H2O
(aldehyde) (salt) (salt) (Manganese dioxide)
6. ATTENTION!!!!
a), b) The addition of NaOH should be very carefull. First of all the amount depends on the raw spririt quality - in particular on the content of acids and esters. Once you put to much you can end up with completely undrinkable product even after distillation. DON'T add NaOH to mash!!!
c) We are talking about KMnO4 (hypermanganate) and not MnO2 (Manganese dioxide). The pH of the liquid should be slighly alcaline (otherwise th oxidation of the alcohol may take place - which is very likely in an acidic conditions). The MnO2 doesn't act as the oxidizer - at least not in alcaline conditions - so there is no danger of creating soluble Mn2+ salts. It may act as an adsorbent absorbing some impurities.
MnO2 is commonly used for water treatment (with purpose of getting rid of Mn2+ and Fe2+ ions). The reaction is an oxidization leading to insoluble forms (Mn4+ and Fe3+). But, as far as I know, MnO2 acts only as a catalyst (helping to oxidize Mn2+ and Fe2+ with the oxygene present in water) and finally doesn't take part in a chemical reaction
If I am right the MnO2 itself will not help you much in alcohol purification (except negligible adsorbing action).
In order to sleep well not worrying about the purity of KMnO4 you should use a pharmaceutical grade which you can buy in any drugstore (the Latin name of this stuff is Kalium Hipermanganicum).
Of course once you do the chemical cleaning of your raw spirit you should filter it carefully (or at least decant it from the dark brown precipitate of MnO2.

I would not be afraid of using KMnO4 for the alcohol cleaning - it is commonly used also for disinfection and even mouth washing (very dilute of course). I cannot exclude that theoretically it may have some impact on your health, but I am pretty sure that the impact of the alcohol itself is thousands times bigger.
Anyhow please note that the most potent substances are natural (not "chemicals").
7. REWARD
Please find below the data from laboratory analisys of the raw alcohol before and after the chemical treatment.

Before chemical cleaning After chemical cleaning
Alcohol content % abv 88,9 89,2
Acids content mg/l 40,9 13,5
Esters content mg/l 509,6 59,2

You get not only cleaner stuf - but also more of it.

Of course the next necessary step is distillation.

8. Common sense.
Listen and think. If you are not sure - ask. Try carefully. Find the border line. Build up your own experience.
Don't be afraid of chemistry but pay attention.

Thats all for now

andre.silent
Last edited by andre.silent on Mon Nov 10, 2008 3:00 am, edited 1 time in total.
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Re: Chemistry help (Manganese Dioxide)

Postby manu de hanoi » Thu Nov 06, 2008 8:30 am

that's a hell of a fifth post Andre. +1 :)
PS: you still haven't read the pm I sent you 4 month ago :) It's the "message" link on top of the page.
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Re: Chemistry help (Manganese Dioxide)

Postby muckanic » Thu Nov 06, 2008 8:00 pm

andre.silent wrote:a), b) The addition of NaOH should be very carefull. First of all the amount depends on the raw spririt quality - in particular on the content of acids and esters. Once you put to much you can end up with completely undrinkable product even after distillation.

Please find below the data from laboratory analisys of the raw alcohol before and after the chemical treatment.

Before chemical cleaning After chemical cleaning
Alcohol content % abv 88,9 89,2
Acids content mg/l 40,9 13,5
Esters content mg/l 509,6 59,2


An aldehyde analysis would have been useful. After constructing some redox half-reactions, it appears that permanganate oxidation of ethanol to acetaldehyde is a net producer of OH-, whereas permanganate oxidation of acetaldehyde to acetate consumes OH-, and hence could be favoured under basic conditions. However, redox potentials also presumably come into it, and that sort of information about whether ethanol oxidises easier or harder than acetaldehyde is not widely available. In practice, it is not clear that the acetaldehyde content of untreated spirit is a big problem, due to its relatively low boiling point (unless azeotropes are involved). So we are presumably talking about eliminating higher aldehydes, no? Secondly, permanganate in excess will create acetaldehyde and possibly other aldehydes, regardless of whether the conditions are basic or acidic, and so there remains the problem of knowing when to stop. Is it proposed that any acetaldehyde is cut out on the second distillation?
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Re: Chemistry help (Manganese Dioxide)

Postby andre.silent » Mon Nov 10, 2008 2:29 am

Hi,

Every experience is related to the particular case.
1. I forgot to mention sending my comments that my experience is related to continuous stripping run.
In such case I end up with low wines which contain all components being present in mash (also aldehydes).
This is more or less smilar to the industrial production when during the initial production of raw spirit nobody cares to get rid of any impurities (this is done afterwards during the rectification).
2. The second remark is that I was interested in neutral spirit only.

For those reasons I found using NaOH/KMnO4 treatment as very usefull tool.

If one does the batch stripping run, then probably some esters/aldehydes are rejected already at the very beginning, so the chemical treatment of such made product is not very necessary any longer.
However there are still some traces (aren't they) and I think that it would be good idea to give it a try anyhow.


The most important question is the amounts of reagents.
Lets take an average raw ethanol composition (please see the remark 1) which of course may widely vary from case to case:
aldehydes - 50 mg/l (calculated on 100% ethanol)
esters - 300 mg/l
acids - 100 mg/l
The rough calculation leads to following amounts of chemicals:
NaOH - 250 mg/l
KMnO4 - 120 mg/l
These results are very approximate as they are calculated on the assumption of stochiometric reactions (which are abviously not - as they are equilibrium and require some excess of reagents).
Anyhow you can easily notice that these are very small amounts.

Moreover I would suggest to use even smaller amounts (at least at the beginning) to see what the results are.
If the low wines is done batchwise than probably figures expressing amounts of impurities are substantially lower - automatically amounts of reagents should be lower (perhaps the KMnO4 is not necessary at all) - in this way a totally agree with muckanic
Re: oxidation of aldehydes posted by muckanic:
However, redox potentials also presumably come into it, and that sort of information about whether ethanol oxidises easier or harder than acetaldehyde is not widely available.

I am not good enough in organic chemistry to give any scientific explantion but I remember that aldehydes are considered to be reduction agents while alcohols are not (therefore aldehydes must get oxidised easier than alcohols).

Again: everybody should do some experiments.

Wnen you do the batch stripping run or even you go for flavoured product (whiskey, rum or whatever else) you may find this chemical tricks useful for cleaning up foreshots and heads (just like manu de hanoi mentioned in his post)
In order to compare the purities of alcohols
I did some tests with KMnO4 by measuring the time it took for several alcohols to react and remove the purple color, and indeed tails & 1st pass distillates would bleach much faster than the final product.

to be able to recycle them to next batches (you should do it with care but as this is usally a waste material you may experinment as you wish).

Good luck

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Sodium Percarbonate? (was Chemistry help (Manganese Dioxide)

Postby helmingstay » Mon Jan 26, 2009 12:51 am

A wonderful thread, if mis-named :)

Can I inquire about using Sodium Percarbonate, Sodium Carbonate, and Sodium Silicate, aka oxyclean or "one-step sanitizer" as a more gentle oxidizer?

Personally, I'm a big fan of using non-toxics like baking soda in dirty low wines - if i add too much, no one dies! I had close calls with drano-bombs as a kid (tinfoil, granulated drano, and a splash of water in a 2 liter, screw it shut, shake, and toss. No, we didn't wear safety goggles...), and I steer clear of the strong-and-nasties now in my modest and decidedly un-analytical laboraratory.

There's been a long discussion about the relative merits of both baking soda and Sodium Carbonate in this forum as error-safe (and aluminum-safe?) substitute for NaOH. So I've got a *lot* of "one-step" sanitizer that I believe contains some combination of sodium percarbonate, sodium carbonate, and sodium silicate. It's sold as a no-rinse beer bottle cleaner, so I'm assuming it's "food-grade".

So, 3 questions:

1. Is Sodium Percarbonate a useful oxidizer of nasties in a slightly alkaline solution of low wines?

2. Can anything in the sanitizer/oxyclean (other than fragrance) make it into vapor phase and out of the pot? They're all non-volatile salts, right?

3. Should this be allowed to sit for some time before re-distilling, and will anything terrible happen if I leave it unattended for a day?

I'm hoping to experiment with some very unpleasant feints this week. I'll let y'all know how it goes...
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Re: Chemistry help (Manganese Dioxide)

Postby pHneutral » Mon Jan 26, 2009 2:30 pm

You know, considering the possible side effects of this sort of thing, and the potential expense, do you think it might be simpler to try auto-oxidation instead of chemical oxidation?

What I mean is, just make a fine bubbler and submerge it in your stripped wash, or final product, and bubble pure, dry oxygen through it for 5,10,15,20,25,30 minutes and see what it does? Try for an hour at lower flow. That sort of thing. Run the O2 through a pile of CaCl2 in a jar to make sure it's reasonably dry.

O2 is cheap.. you can even make it by cracking it out of water with electrolysis and use that for your auto-oxidation. Just vent the H2 pretty well :)

Seems a bit simpler than using all sorts of oxidizers, especially considering we're not going for commercial here (I'm assuming).
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Re: Chemistry help (Manganese Dioxide)

Postby helmingstay » Mon Jan 26, 2009 6:47 pm

pHneutral wrote:You know, considering the possible side effects of this sort of thing, and the potential expense, do you think it might be simpler to try auto-oxidation instead of chemical oxidation?
[...]
O2 is cheap.. you can even make it by cracking it out of water with electrolysis and use that for your auto-oxidation. Just vent the H2 pretty well :)

Seems a bit simpler than using all sorts of oxidizers, especially considering we're not going for commercial here (I'm assuming).


I've been bubbling my finished, flavored products every 6 months or so ~30seconds, since they're packaged in glass and don't get much oxygen otherwise. At that rate, an $8 tank from Lowe's should last me 5 years.

Bubbling product for an hour, though, requires buying an oxygen tank, getting it filled, venting the oxygen, *and* takes an extra hour.

Making oxygen via electrolysis? *Really* bad idea:
1) Extraordinary waste of electricity ( @ 65% efficiency, something like 10 kWh/Nm3? I ripped some specs from here - http://www.global-hydrogen-bus-platform ... ectrolysis)
2) Hydrogen is explosive. Oxygen only makes it more so...
3) Electricity + water can be dangerous for the inexperienced
4) Cost of electrodes?
5) Common electrolytes are dangerous chemicals: "The electrodes are placed in an ion-conducting electrolyte (usually an aqueous alkaline solution with 30 % potassium hydroxide KOH)."

I agree, KMnO4 seems pretty sketchy. Baking soda, on the other hand, is tried and true and, to my palette, tasty. Sodium percarbonate seems much closer to the "do no harm" end of things...
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Re: Chemistry help (Manganese Dioxide)

Postby muckanic » Mon Jan 26, 2009 7:04 pm

I suspect finding purish H2O2 would be easier than finding pure percarbonate. With any luck, liquid peroxide stabilisers wouldn't muck too much up. None of this constitutes endorsement of the whole notion that chemical oxidation reduces congeners. :o
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Re: Chemistry help (Manganese Dioxide)

Postby helmingstay » Mon Jan 26, 2009 7:20 pm

muckanic wrote:I suspect finding purish H2O2 would be easier than finding pure percarbonate. With any luck, liquid peroxide stabilisers wouldn't muck too much up.


I checked a package of Oxo Brite (http://www.ecos.com/pages/oxo.html) this morning, and there are 2 ingredients listed: Sodium Percarbonate and Sodium Carbonate. Is the concern that there are minor amounts of contaminants that could potentially volatilize, or contaminants that could react in the pot? I'm a little confused.

A quick search shows that any H2O2 you can buy is *not* pure. All sorts of weird things added to stabilize H202. And H2O2 in any concentration is pretty nasty stuff. And buying it from the drugstore at 3% by the quart sounds expensive, not to mention that it adds needless water that's going to be stripped out anyway.

muckanic wrote:None of this constitutes endorsement of the whole notion that chemical oxidation reduces congeners. :o


Fair enough :)
Anyone qualified to comment?
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Far better an approximate answer to the right question, which is often
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