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Author: Subject: Destructive Distillation of Wood
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[*] posted on 7-10-2004 at 17:41
Destructive Distillation of Wood

Anyone tried this? I've experimented with it a couple of times, got the textbook results more or less.

Here's a drawing of the basic concept that I found online:

I used a glass jam jar to hold my wood (sawdust, actually) and heated it over a propane stove. A tube led through the lid of the jar into a bottle that was cooled in a bath of snow + water. Also, I led some of the tube through the snow/water mix to get more cooling.

Initially it appears that water was given off, some of which condensed in the bottle. After it was dehydrated, a very dark liquid started to come over, accompanied by large amounts of gas. Judging by descriptions I have read of this experiment, the liquid was tar, acetic acid, and methanol, while the gas was methane, probably some CO, and methanol vapour that did not condense. The gas burned readily (as one might imagine!).

I was forced to halt the procedure before completion, because the seal between the jam jar and the lid was burned away, and the whole thing started spewing some flames, which my parents (watching with mild interest) decided was the limit.

The liquid I got was very rich in tar, presumably because I used a large portion of softwood (can't pick and choose your sawdust in Dad's workshop :D) . It was definitely acid (decoloured a sodium carbonate/phenolphthalein solution), presumably acetic acid. I was unable to determine methanol content, but I assume it was there.

It seems that thermal decomposition of wood might be something worth playing around with more. Methanol and acetic acid are definitely useful, I’m sure some applications could be found for the wood gas (home made Bunsen burner fuel? :P), and the tar could at least be used for making seals, I suppose?
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National Hazard

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[*] posted on 7-10-2004 at 22:01

Welcome to SMDB Oxydro! For a newbie your post is clear and detailed; good job.

Don't heat jam jars expecialy not with a propane jet!!:o They are not made to take the heat and can shatter.

I don't know much about DD of wood but something tells me that no one bothers with it on a small scale due to low yield for fuel/time expended and impure product. You can very easily get acetic acid in 5% and stronger stuff is only slightly harder to come by. Methanol can be had as Heet brand car fluid(in the USA)

My suggestions for you is to get a good collage level book of general chemistry. Read it and do the problems. This will help you understand of what we speak and allow you to accuatly experement. If you want to then you can get an organic chem book but be warned its hard to learn. However read the words of Shurigin:

"Leave the orbitols for mathmetitions; chemistry is for people that like to cook"

You will like this site. It has tonnes of OTC(over the counter) products and the chemicals they contain

I will now explain a bit of the culture here.

This site along with the hive and make up a core 3 sided shape of online chemistry type stuff.

The hive is where Bees make honey(drugs) These are not your common idiot meth makers by far. Some of the best organic chemists online live there. Perhaps Primopyro can act as a spokesman here?

Rougesci is a place for explosive and weapons makers. It was shut down by a freedom hating company called IDefence but has come back.

This is a site for pratical chemistry discourse about everything else. Don't talk about the ergot you just got or the AP det you just made. We don't talk about it here.

Watch out for vulture! He will stomp you if you turn kewlish(lame and unsafe newbie) but I don't think you will so don't worry. Look at Chemleo, BromicAcid, madscientist, Polverone(admin in cheif) ext. Just about everyone here has good ideas and information.

There is a whimsy area for random talk. Ask an admin for the password. Here you may find moonmonster(a strange and warped but funny guy) and if_6_was_9 a radical right winger type.

Take care, have fun, don't blow yourself up!


What if, what is isn\'t true?
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[*] posted on 8-10-2004 at 03:32

Oh, I know it's easy enough to purchase both methanol and acetic acid; in fact, methanol, for example is available to me for about $2.50 /liter (Canadian), labeled as such, marked "guaranteed pure", at the local Co-op.

The idea was just that it's another thing that can be made by the amateur; not because it has to be, but simply because it can be. For fun, in other words. If nothing else, separating it would involve a very interesting distillation. Sorry, I didn't really explain myself very well in my previous post.

BTW, regarding the jam jar, I had it wrapped in old screen just in case. It did end up fracturing as it cooled.

Thank you for the advice etc. I've actually been around for a while now - registered a few months ago and have been reading regularily and posting occasionally. I've been a member of RogueSci longer, but I've drifted away from their weapon orientation. I only recently started visiting the Hive.
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Biochemicus Energeticus

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[*] posted on 8-10-2004 at 09:29

Apart from wood itself, which is well-known to produce methanol (this is why, in German, methanol is also called 'Holzgeist', or 'woodspirit/ghost';), I wonder what the destructive destillation of green material (leaves) will produce. Mainly water of course... but surely a fair bit of acids.
One limitation is of course that the destillation will require the distillate to be volatile. The rest will just decompose, into various organic gases.

Another thing one could do is subject wood, green material etc to strong acids and boil them. I am sure you'd get various interesting sugars, and amino acids from it.

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Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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[*] posted on 8-10-2004 at 15:37

Destructive distillation of wood is used to obtain wood creosote, or wood tar, used as a timber preservative (although it biodegrades after a while, and its major ingredients, the three cresols, are slightly soluble in water), and as a topical veterinary fungicide and disinfectant (e.g. for scaly feet in chickens). This is along with methanol, which being more volatile can be mostly distilled off, along with small amounts of ethanol and higher alcohols and furfural (and traces of others like pyran). The dark color is due to small amounts of high-molecular-weight polynuclear aromatic hydrocarbons.

John W.
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