Distillation Daydreams

I daydream about recreating human technology on my own. I've thought about it basically every damn day for years. I don't know how to stop. Maybe writing about some of it will help? It never has before. Maybe I'm just spreading bad thoughts by writing this. Consider not reading this if you don't want to daydream about recreating human technology on your own, every damn day for the rest of your natural life.

Lots of wonderful things can be made or purified through distillation. Some examples:

* Ethanol. If you let yeast ferment sugars into alcohol, you can concentrate the alcohol. Whiskey, brandy, rum, mezcal, vodka, et cetera. Also, you can let your fermented sugars spoil to get acetic acid and distill that out if you like.

* Essential oils. If you boil water and there are a bunch of flowers or pine chips or other plant material in the way of the steam, the steam can absorb some terpenoid oils, and condensing it down lets you make perfumes. Or home remedies for autism or something? I don't know what foolish people do with essential oils. Just use it for perfume. Or use it to flavor your vodka to make gin or limoncello or vanilla extract. But a little bit goes a really long way.

* Mineral acids. A bunch of sulfate minerals can be heated/roasted to produce sulfur trioxide vapors, which can be condensed in water to produce sulfuric acid. The traditionally used sulfate minerals (vitriols) aren't globally uncommon, but it's not like you're going to find them in quantity in your backyard or a river bed or a roadcut. The vitriol minerals are all sulfate salts of heavy transition metals (copper, iron, cobalt, zinc). The more common sulfate minerals on the earth's crust are evaporite deposits of sulfate salts with light alkaline metal cations. I think gypsum (hydrated calcium sulfate) is the most common sulfate mineral. Alchemists didn't use it to make sulfuric acid, but I've heard of it being done in modern times, so maybe it's just difficult? In the 1970s, the Marchon Chemical Works in Whitehaven, UK made sulfuric acid and calcium silicate by roasting gypsum with siliceous rocks. I think it required very high temperatures., since calcium sulfate and sodium sulfate both have thermal decomposition temperatures around 1100 deg C. Eventually, Marchon gave up on gypsum and switched to roasting elemental sulfur, but still, gypsum is some kind of an option, if not necessarily a good one. Other alkaline sulfate minerals found in evaporite deposits include epsomite (magnesium sulfate), baryte (barium sulfate), and thenardite/mirabilitie (sodium sulfate). Alum minerals (double sulfate salts that have both aluminum and an alkaline metal as cations) are also sulfates, and I think they're intermediately common between alkaline sulfates and transition metal sulfates. I don't know how hard it is to make sulfuric acid out of alum by heating. It's probably easier to make sulfuric acid from most of these by electrolysis than by distillation, but that's not an option in the first stages of my fantasy. Whatever the source, once you have made sulfuric acid, you can mix it with other minerals and then distill the mixture to make new exciting mineral acids .Sulfuric acid plus table salt, distilled, gives hydrochloric acid. Sulfuric acid plus nitrate minerals, distilled, give nitric acid. Glauber figured both of those recipes out. Thanks, Glauber. Sulfuric acid combined with with phosphate minerals gives phosphoric acid. Et cetera. It's a very useful chemical, that sulfuric acid. Also you can make sulfuric acid by roasting elemental sulfur or metal sulfide ores, instead of roasting sulfate minerals, but there are some extra steps. It's called the Lead Chamber Process and you have to control the mixing of three gasses and a sprayed liquid. It's not the easiest way to start out your technology recreation fantasy.

* Wood liquors. If you heat up wood in a low oxygen environment (pyrolysis, pyrolytic decomposition, destructive distillation), then gasses and vapors come off and you're left with charcoal. If you condense the vapors, you first get pyroligneous acid, which, besides water, is mostly made of acetic acid and methanol, and a decent amount of acetone. I've read that the distillation of cellulose gives acetic acid and the distillation of lignin gives methanol. Super interesting if true, right? But maybe a little misleading in its simplicity; cellulose is a polymer made of glucose monomers. When you heat it up to thermal degradation in a low-oxygen environment, acetic acid might be the first volatile to distill over, but lots of caramel-like stuff with a higher boiling point is being made in the pot. Likewise, lignin is an irregular polymer made of aromatic alcohols, and methanol might be the first and the main volatile given off by the pyrolysis of lignin, but it's not the only one. Anyway, acetic acid, methanol, and acetone all have some uses, and you can separate them out by fractional distillation (i.e. redistill the mixture with more precise temperature control and with a taller column in the still to encourage reflux). This whole post came about because I was looking into low-tech ways to get methanol for use in biodiesel transesterification. In addition to those three components, your pyroligneous acid will contain a million other random smoky caramelly tar-like organic contaminants in small amounts: formic acid, furfural, pyridine, methyl ethyl ketone, the list just goes on and on. As you keep heating up the wood, tar will start to come over with and then after the pyroligneous acid. Or I guess it could all come over at the same time, if you heat things up quickly or if your still doesn't have any real height for refluxing. If you let the distillation products cool and settle, the tar will be the viscous part at the bottom and the pyroligneous acid will be the runny part at the top. Tar is another wood liquor with some uses - like preserving ship timbers from rot -  although I mostly think of it as contaminant when trying to distill more valuable things. Similarly to distilling wood, if you distill pine resin, you can get turpentine.

* Ammonia. Lots of organic matter has amino acids. Animal tissues in particular have a lot. Amino acids can be distilled to make ammonia gas. Condense it in water and you've got ammonium hydroxide. It's good for cleaning, it's good as fertilizer, it's a decent refrigerant, and it can be used to make hydrazine rocket fuel. And ammonium hydroxide is a convenient base in chemistry and it's in hair dye and other stuff. Lots of uses.

* Low boiling point metals. Some metal can be boiled/vaporized pretty easily and separated from their ores that way. Mercury and lead are pretty easy to distill off of their ores, for example. And at higher temperatures,  you can do more metals. It's pretty cool.

* Petrochemicals. If you have crude oil, which some places in the world do, you can distill it to separate out hydrocarbons by boiling point. Now you can use hexane for acid-base extractions or make candles out of paraffin wax or other things. I hear gasoline has some uses. You can make stuff that like. Petrochemicals can also be made by the Fischer-Tropsch process, although that's not something we do till a much later stage in the tech fantasy.

So there are all these amazing things you can get by heating up plants and rocks and animal tissue in a vessel and condensing the vapors. But how do you do actually distill those things?

"You buy a laboratory glassware distillation apparatus online." No. We're recreating technology on Mars or in the distant past or something. You don't get a glassware supplier. 

"You buy a... copper still online?" Still not quire there.

"You make your own copper still!" Much better! But I'm not very good at metal working, and also, where are we getting all this copper from? Have you ever mined copper? Do you know where to mine  copper? That's not a real plan. 

Honestly, it is a start of a plan. We could make aqueducts to hush the loam from the countryside, revealing bedrock, and then melt ores by fire-setting, maybe. Or we could crush rocks down by a river with a waterwheel and a hammer on a cam follower and then separate out the crushed rock according to density by gravity methods, and in that way find some heavy metals. I don't mean to say that mining isn't possible. But it's not easy and you don't have any guarantee of what you'll find in what places, and it's not usually one of the early steps in my primitive technology daydreams.

The low-tech way to distill things on your own, without a global economy that can extract copper from distant lands and transport it to you, is to make a still from clay. Clay is easy to find, in the distant past, or in your backyard, or even on Mars - all the usual daydream locations - and it's moderately easy to work in a primitive setting, especially compared to metal or glass.

It's a little dangerous to distill alcohol in clay, because the clay could shatter and now you're suddenly throwing alcohol on a fire in an enclosed space, but people in Mexico still make mezcal with clay plots; it's not an insurmountable risk. And it's not like distilling alcohol in metal or glass is without risk. 

The old-timey names for a still are an alembic or a retort, depending on whether it's made from multiple pieces or just one. If you use clay to make a still, and your still has more then one piece to it, with the pieces just stuck together through friction fitting - like a lid on a pot - then the still probably won't be airtight, and your vapors will come out the cracks instead of condensing where you want them. One ancient solution for this is to use dough to plug up holes. It cooks into a horrible little papery hardtack biscuit whish stops gases and vapors from escaping for a while. If your dough-plugs shrink too much as they cook and dry, you can just put on another rolled up snake of dough to plug the new gap. I've done that before with a metal still that was venting steam and I don't really ever want to do it again. What are some other options?

One option is to use a still that only has one piece: a retort. It's a kind of teardrop shape, and the tip bends over and away from the bowl at the bottom to form a condenser tube. Retorts are cool. Hard to clean out though. Kind of hard to fill with solids like animal tissue or woodchips too. I think there's another option.

What we have illustrated here above is a two-piece alembic. The only joint at which we need to stop gasses from venting out is the one where the conical upper piece meets the groove of the lower bowl. Here, the groove is filled with water to help with sealing; I think that's important. You could also put more things in the groove, if you wanted. Like sand, maybe. Or dough snakes. Pine pitch. I don't know. But I think a two-piece alembic makes cleaning and charging the vessel a lot easier than in the case of a retort, and maybe its single joint is a manageable challenge to engineer around, especially if you have a groove full of water, rather than just a friction fit between a pot and a lid. I suppose you could also put grooves on the upper piece and thereby make a little serpentine maze of traps. I don't thing that would help much, but maybe.

Some of the cool distillation products listed above are gasses at standard temperature and pressure and they need to be dissolved in water to make them easily storable and usable, like SO3 becoming sulfuric acid in water or NH3 becoming ammonium hydroxide in water. But if the condenser tube is leading into a container of water, and the seals of the groove also contain water, is there any reason to think that the valuable gas will go in the water that we want, instead of out the side? I don't really know. My hope is that, for example, water can only hold so much ammonia gas, and so the little bit of water in the groove will quickly become saturated, and then the larger amount of water under the condenser tube (not pictured) could keep collecting ammonia gas, and the gas wouldn't start escaping from the system until both reservoirs of water are saturated. I don't know if that's how gas actually works. If that doesn't work, I guess dough snakes are fine. I'd still probably try water and sand first. Or maybe use some wet unfired clay as a plug, in addition to water.

Wait a second, that's not how gas woks at all. You can bubble carbon dioxide though water for a long time and barely increase the carbonic acid content.

This leaves me with a few things I need to figure out to advance the narrative of my primitive technology fantasy, as it pertains to distillation, in the early stages of the fantasy before I've built up resources I need for metal- and glass-working. 

1) I need to prove to my satisfaction that I can make and fire a two-piece clay alembic with a groove for water sealing.
2)  I need to learn more about making sulfuric acid by distillation, either from common evaporite minerals like gypsum, or from elemental sulfur or sulfide minerals. I wouldn't be surprised if there was a good technique that I'm just not seeing in the historical literature or patent literature - maybe something that's too expensive for industry but it works at lower temperatures than the Marchon system.
3) I need to learn more about how gasses work, with respect to, like, partial vapor pressures and solubility and things. I've tried before and it's so boring it just passes between my ears, but maybe having a project on which to use the knowledge will help.
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Another option that is basically materially equivalent to a clay alembic sealed with uncured clay, but on a larger scale, is to make a kiln out of fired clay bricks and seal it up with mud and straw. You'd still have to figure out a condenser design though. Maybe you could have a side chamber a ways away from the heated portion for liquids to condense or for gasses to dissolve into water. Or, I've heard that if you have a sloping hole out from the bottom of a a kiln where you distill wood, you can get pyroligneous acid and tar to just flow out on the floor. Maybe that works for other some things too. Probably not ammonia and SO3, because they have to be dissolved in water. But maybe some things. Or just make a ceramic tube and put it at the top of the kiln instead of the bottom. Lots of mud to seal, a tube leading into water, done.

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