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Ethanol can of course be distilled from grain, potatoes, whatever, but if you're going to drink the stuff, its toxicity aside from its ethanol content should probably be fairly low. In the meantime, crops which could potentially be eaten, though i suspect there are different standards involved, are
in a sense wasted as fuel, which might be more profitable and drive up the price of the crop as food.
In the case of fuel ethanol, the problem is the other way round: how to stop it from being consumed by people. One way this is done is the addition of mineral oil derivatives to make it more toxic. This means that even fuel ethanol relies on the presence of mineral oil, which is not sensible.
However, for all we know at least if not more so, there are plenty of poisonous plants which are not toxic to yeast and therefore can be fermented, such as water dropwort and cuckoo pint root stocks, deadly nightshade and so forth. An issue is whether the toxin can also be distilled, and if so, whether it would inhibit oxidation. Even if not still toxic, they could thrive, perhaps pest-free, on land unsuitable for farming due to pollution or poor soil, and still be useful for fuel. Why waste food?
Methanol Poisoning
http://www-clinphar...poison/poison9.html
[MikeD, Feb 26 2010]
R vs K
http://en.wikipedia.../K_selection_theory
[bungston, Feb 26 2010]
Gribbles
http://www.timesonl.../article5600646.ece
Cellulose to sugar (to ethanol) [nineteenthly, Mar 09 2010]
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And yes, cuckoo pint root is edible when cooked. Hemlock isn't. Pretend i said that. |
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The traditional additive to poison alcohol is 10% methanol. Currently primarily produced from natural gas, but originally produced by the destructive distillation of wood. Where does mineral oil come in to it? |
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Mineral oil has been used, [Loris], don't know about now, i think in Brazil. |
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//The traditional additive to poison alcohol is 10% methanol// |
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Odd. The antedote to methanol poisoning is ethanol. |
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Huh. I understood that the most common poison/adulterant of ethanol intended for addition to gasoline is ... gasoline itself, which is a mineral oil product, depending on your local language. Which totally messes up all quotes about the energy in a gallon of ethanol--is it pure alcohol, or is it ten-percent of the more energetic gasoline? |
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I did quite a lot of research into ethanol a couple of years ago--well, web surfing, mostly, nothing in a lab--and ran the numbers on what I found. I concluded that making ethanol is a big waste of time, money and food. It is better by far to make a biomass-fueled electrical generating station, or make a steam car fueled by corn kernels, or even to make some other kind of alcohol that works better in gasoline engines (I forget which that was). |
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This idea, of using poisonous plants as feedstock, is clever. The problem seems to be that ethanol just isn't worth making, but if it could be made from cheap, undesirable plants, and the cost and trouble of rendering it poisonous avoided, it might be made economically. And this idea is half of how to do that, so it gets a bun with only a little bit of nightshade accidentally mixed in. |
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1: I do not like the whole thought process behind denaturing alcohol. The only reason to do this is to support excessive tax structures or moralistic legsilation. |
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2: I like the idea of cheap and undesirable plants used for feedstock. The thing about poisonous plants is that if they invest in poison they are usually fairly k-selected - that is the plant is slow growing and slow to seed so the energetic investment in protecting the parent plant is worth it. Ethanol feedstock should be r selected weeds: crazy fast hell-bent-for-leather get the seeds out and who cares what happens in the meantime type plants. Reed Canary grass is one of the better candidates for this I have run across. |
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Ethanol is an antidote to methanol poisoning because it keeps aldehyde dehydrogenase busy while the methanol gets eliminated, (which can be speeded up by dialysis), stopping it from getting converted to formaldehyde but unfortunately not doing anything about the CNS depressant action. |
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And indeed, ethanol is not particularly efficient as a fuel given its "life cycle". It's a waste of food if it's made from food, but this wouldn't be. Biodiesel from food crops drives up the price of food because it's worth more as biodiesel. Whether it's a waste of money depends on how you get the resources, though it could become a waste of time instead. To my mind, the chief barrier here is the illegality of stills. The easiest aliphatic alcohols to make from biomasse seem to be methanol, ethanol and butanols. I don't think the propanols are feasible - did consider doing things starting with onion juice and yeast but got no further. |
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Biodiesel from poisonous plants might be feasible. |
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1: Totally agree. However, it's only one reason, and i suspect there are relatively few compounds whose boiling point and concentration in a plant are both high enough to carry across, so that particular bit of the plan is probably a bit ropey. There would be a few sesquiterpenes and so on, but those are neither concentrated nor very toxic. Alkaloids i would think have high boiling points, glycosides would break down (wouldn't they) and tannins would either sit there or inhibit the yeast. Complex issues there, maybe because for a change i actually know something about the subject. |
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2: Thanks for that, it'd never occurred to me before. Lots of poisonous weedy herbs about of course, but hemlock and water dropwort would clearly be worthwhile. Yew berries? Whatever else |
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One more thing about this: is it ever easier to do this rather than generate methanol from woody plant parts growing on scrubland and the like? |
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I [+]'d this 'cuz it's an interesting idea, but realistically if you wanted to drink it you'd just have to distill the ethanol out whether it's mixed with methanol or whatever... might make things a bit easier for moonshiners (mmm lead poisoning), and high-school chemistry classes would be a blast, but apart from that... |
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Why was methanol de-emphasized: too toxic/explosive ? |
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I can never remember which way round alcohols are, whether it's lighter=more energy or the other way round. Would methanol have higher vapour pressure? |
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Something else has just occurred to me. If you were able to distill a mixture of rose petals and rosehips this way, you might get a rose-flavoured spirit liquor. |
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How about this? Take the some of the alcohol, however you make it, and soak the poisonous plants in it to leach out the poisons into the alcohol. If too much other crud comes out, distill the alcohol again and process the leftovers for the desired poison. |
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I mean, most of the facilities are already in place, and the leached-out plants could be added to the mash again, or even burnt for fuel in the factory. |
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By the way, poisoning alcohol isn't really meant to keep someone from re-distilling it, is it? I thought it was just to keep drunks from chugging it, but there might be money in cleaning it up in bulk, come to think of it. |
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Now that really _is_ baked, several times over, in a locked cupboard in the room next door, [baconbrain]. |
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Oh, and the second point: i see the purpose of denaturing alcohol as stopping people from drinking it or selling it on as a beverage, but there are issues there because whereas i'm teetotal i wouldn't want to stop someone else drinking it, and in the case of alcoholism, which is rife in my family and has led to fairly severe violence and a number of deaths from alcohol-related causes, i would still see it as self-medication in some cases. |
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//Huh. I understood that the most common poison/adulterant of ethanol intended for addition to gasoline is ... gasoline itself, which is a mineral oil product, depending on your local language. // |
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That's probably a language issue then. My understanding is that mineral oil is a byproduct of gasoline (a.k.a. petrol) production. Incidentally, Wikipedia agrees with me - and further, it's not even toxic, being present in baby oil, cosmetics, taken as a laxative etc. |
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I agree that it would be hard to find a natural toxin which distilled with the alcohol in any case.
I suppose it might be possible to find or engineer a yeast to produce more methanol ... or propanol or some other alcohol. |
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I believe the reason people are producing ethanol from 'food' at the moment is because the process basically converts the sugar and starch content to ethanol. And the best source of those are crops which have been selectively bred for that for thousands of years, i.e. food crops. |
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Further to that, utilising the other polysaccarides (cellulose, mainly) would clearly be a major improvement, and that's an area of active research. |
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I think it would be entirely possible to breed (or engineer) a crop specifically for fuel production - with improved pest resistance via toxins which make it inedible for humans too. But then there'd be a constant concern about contamination of the food supply. |
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I use the term "mineral oil" to distinguish the immiscible viscous liquid found underground and in seepages and its liquid derivatives obtained by fractional distillation from the fixed and volatile immiscible viscous liquids derived from living or recently dead products. So, for example olive oil and attar of rose are not mineral oil, but octane and petrol are. |
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There are some pretty huge rootstocks in wild plants. Wild parsnips take about ten generations to reach the point where they do the carrot thing. Hemlock and water dropwort are already like that in the wild state. Horseradish, though it would be a shame to treat it as a mere fuel crop, has an absolutely massive root stock like several ram's horns joined together. We're not talking titchy, weeny little sources of carbohydrate here. The things are often bloody massive. |
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Ironically, i think the easiest thing to do, provided the mustard oil didn't interfere with the yeast, would be to use horseradish. However, it's such a good source of other things it would be a bit of a waste. |
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Oh yes, but those are unusual. Most biochemical toxins are destroyed at that temperature, though come to think of it alkaloids generally don't seem to be - nicotine, morphine, and cocaine. Coniine is clearly in that category. |
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In that case the question is, are there plants with a high calorific value which contain toxins easily destroyed by heat? The crucial ones that i can think of right now would be horseradish and poisonous umbellifers, mainly because poisonous fruits tend to be small. Still, if you can make blackberry or elderberry wine, maybe there are still possibilities. |
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Can these plants be grown, industrial-scale, on otherwise
barren land? Otherwise, this is a proposal to divert arable
land use from production of edible to poisonous crops.
Already, there are complaints about diversion of corn from
food to ethanol production. |
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//The problem seems to be that ethanol just isn't worth making, but if it could be made from cheap, undesirable plants, and the cost and trouble of rendering it poisonous avoided, it might be made economically// |
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If you are not too bent on the whole poison plant angle, then hemp biomass has about four times the cellulose of corn, it's not edible, requires no pesticides, and grows like uh weed. |
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A question, perhaps not related enough ... |
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Aren't most strains of brewers yeast developed to convert starches and sugars into alcohol? I know there's a step there I'm leaving out, but generally speaking, most of the tame yeast we have are bred to convert food to ethanol. |
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We really don't have many yeast strains that convert cellulose to alcohol, right? I don't know if that is even a feasible step, chemically speaking. |
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Termites and cows have bacteria that break down cellulose, but they surely aren't making alcohol. Wood alcohol .... |
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<sneaks off to Google for a while> |
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[Nineteenthly], you have huge potential waiting to be
untapped. |
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[MB], there's a whole algebra ready to spring from that sentence. |
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[Mouseposture], i'm talking about land which can't be used for food crops, which actually i did say, or it'd just be the same as food crops for biodiesel. In fact, i'm really talking about land where these plants are already growing. Poisonous weeds, basically, with either large storage organs or large fruits. Come to think of it, a lot of the Asteraceae would be interesting in this way, poisonous or not, because of the inulin. |
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Cellulose can for some reason only be digested by relatively few organisms, such as termite GIT protozoa. However, there must surely be quite a few fungi which can digest cellulose, unless they rely on microorganisms too. |
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[Fries], yes and not only that but fixed oil too. |
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Just had another thought: if a toxin present in ethanol survived burning, it could be purified and used that way, either as a drug or a compound useful in some other way, such as a pesticide. Were it altered by the same process, it could become something useful. So, you have your engine running on horseradish ethanol, then collect the mustard oil from a condensing chamber near the exhaust. Or cocaine. |
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And apparently, mustard oil is already used to denature ethanol. |
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Ethanol can be distilled from grains because the
kernels contain the necessary enzymes to convert
the starches inside into sugars, which will be used
as food for the sprout. The first step in brewing is
to soak the grains in hot water to activate these
enzymes and converting the starch into
fermentable sugars. This is why countries without
important primaries in Iowa make ethanol from
sugar cane.
As far as I know, no one has come up with a way
to make ethanol from cellulose in a cost-effective
manner. Once they do, there's plenty of cellulosic
waste, like corn stalks or wheat stubble, that can
be used to make ethanol without threatening food
supplies (and maybe even lowering prices, as
farmers can now make money by selling waste they
used to have to dispose of). |
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I don't know that it'd be worthwhile. Simply burning the cellulose would yield more energy because its calorific value must be higher than ethanol, so a steam engine, particularly a Stirling one, would seem to be a better idea. The other thing is, once cellulose is converted to sugar it becomes food, so you'd be talking about a process to convert it directly to ethanol, though in a sense that's also food. |
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// I don't know that it'd be worthwhile // |
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It would, because if you wish to run aircraft and independant ground vehicles, you need liquid fuels (or liquefied gas). |
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It's obvious that simply burning biomass will yield more energy than first converting (some of) it to ethanol before burning that.
The advantage that ethanol has is that being a liquid it is easily transferred and used in small-scale engines. So it is a replacement for petrol (gasoline) in cars &c rather than large-scale electricity generation or space-heating. |
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I'm not sure why you're so bothered about whether something is edible, nineteenthly. It doesn't make the process any more efficient if something is indigestible. Producing biofuel from crops may not be particularly efficient, but that doesn't mean that producing biofuel from random weeds is going to be better. To make it at all tenable you'd have to cultivate the area and grow appropriate plants.
Sure, you could potentially grow stuff capable of living in areas where maize, say, couldn't grow. But the yield won't magically be higher - chances are it'd be a lot less unless you give it the TLC that food crops get. |
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Edibility is a good thing because it means it can be
eaten, [Loris]. I wouldn't be happy if someone had
removed something i was planning to eat and
turned it into ethanol. It might make sense on
polluted land to do that. |
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I don't know about the cultivation issue, because
there are plenty of places covered in Japanese
knotweed or kudzu, though why anyone wouldn't
want to eat the former escapes me. I can think of
large lengths of canal bank covered in horseradish
which would be easily harvested using either a
barge or a trolley. Water dropwort and hemlock
could be similarly harvested, but there'd be no
need to separate them. All that's required is for
them to be ground up and fermented, like parsnip
wine, and then distilled. There's no need for them
to be grown in a monoculture if they're poisonous
anyway. They already grow together in that case
and are easily collected. I've done it with
horseradish. |
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If the ethanol was left out of motor fuel,engines would run better, more effiently, with less maintenance and there would be more food at lower prices. If more beverages at lower prices resulted maybe some of the cars out there polluting would stay home because their drivers would be too polluted to drive. |
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I actually forgot people drank ethanol too! |
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The point is, food is only one of several necessary or desirable resources. You seem to be saying that just because something could theoretically provide calories for someone, not eating it is a waste. No-one is eating straw at the moment - no-one with all their marbles, anyway. Producing sugary sludge from it as a prelude to ethanol doesn't make it particularly appetising - but suddenly it's a shame noone's eating it. |
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You're not even being consistent. The loss of calorific value of fermentation isn't exclusive to edible compounds. |
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The day someone has to scavenge weeds from a canal, grind them up, ferment and distill them then not drink the result is probably the day they start to walk to work instead of driving. |
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Not if they can then sell the ethanol or exchange it for something else. |
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But yes, i am being inconsistent. However, cellulose has other uses, such as making paper, textiles, papier mache, burning as a fuel for heating rather than in an internal combustion engine. Ethanol has other uses too - for instance it could be used as a solvent, an antidote to methanol poisoning or the stuff can be left to become vinegar with all the uses ethanoic acid has. |
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Then again, there's wood gas, though that doesn't generally burn safely. |
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// The day someone has to scavenge weeds from a canal, grind them up, ferment and distill them then not drink the result is probably the day they start to walk to work instead of driving. // - in other words, the day we can't get hold of what i call mineral oil any longer (but there is biodiesel of course). |
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Ethanol is a poor fuel, since it has low energy density and high volatility. It does however have a very high octane rating so can be a good additive. Ethanol is far more valuable as a solvent/chemical feedstock/fragrance additive/relatively non-toxic sanitiser/etc than a fuel since it is pure and amazing (compared to a heavy arab crude for example). I think someone said a steam stirling engine? Say no more. Cellulose can be hydrolysed by enzymes (as has already been said) or by sodium hydroxide or by sulfuric acid. Denaturing alcohol is by no means arduous and at least where I am methyl violet is used rather than methanol. Home stills are also legal here. Shorter chain alcohols have more energy that longer chain alcohols (for the same reason natural gas has a higher calorific value than bunker fuels). All the marginal land in the world could not produce enough crops to provide a reasonable quantity of ethanol. The purpose behind denaturing alcohol is to allow different tax for industrial and recreational users. |
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// Home stills are also legal here // |
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Seriously though, yes, I mentioned the Stirling engine, but those are one of those bits of kit that are always just round the corner. Presumably there is an answer but that's a whole other discussion whose successful conclusion would probably lead to untold wealth. |
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So, as an additive, what happens if it's added to biodiesel? |
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//... I mentioned the Stirling engine, but those are one of those bits of kit that are always just round the corner. //
Oh, come on. The idea was patented in 1816. They're hardly new tech. |
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//So, as an additive, what happens if [ethanol is] added to biodiesel?//
I'm not an expert on engines, but Diesel engines don't work in the same way as petrol engines. I don't think knocking (which is the undesirable property octane rating tells you about) is an issue for them - Diesel fuel has a correspondingly low octane rating. |
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They're not new, but they're not generally practical either. There are also fusion power facilities, but they don't work efficiently. Similar problems with Stirling engines. That said, i like the idea of a Stirling engine running on cellulose waste. |
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See what you mean about the diesel. In that case, um - well, various thoughts but not yet. |
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Not quite the same thing. No-one has got fusion power working (in the practical sense) yet. |
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Stirling engines work just fine. The efficiency may be low, they may not be economically viable, but they're pretty much a known technology at this stage. |
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Ah, but I like the idea of Stirling engines too. I've not posted any thoughts on them here (yet), but many others have. I've got this idea about getting people to sweep up snow from the roads as a cold source for their massive Stirling engines instead of gritting the roads, but didn't quite get to it. |
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See link for a news story on converting cellulose to sugar industrially. |
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That notwithstanding, [Loris], i'm also a fan of Stirling engines, and ultimately they may be a solution to the whole thing which doesn't involve biodiesel. And, should you not have done so yet, i think you should post that: sounds pretty groovy. |
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Just one thing about Stirling engines: As in many other areas, precision engineering scares me, and they seem to need to be pretty carefully made. |
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// Can these plants be grown, industrial-scale, on otherwise barren land? // |
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Blue-green algae. It requires more infrastructure and monitoring than a traditional soil-grown crop, but you don't need any arable soil at all. Yields per acre are orders of magnitude higher than the best land crops, and it can supply ethanol, diesel oil and fertilizer. |
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//Stirling engines: / precision engineering scares me // |
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They operate at low gas pressures though, don't they? If one does pop a seam or blow a seal, it's not going to be like standing next to an exploding steam boiler. |
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Blue-green algae need to be stirred and aren't already there most of the time. They're a very efficient use of space though and i'm now wondering what happened to the algal blooms (which were actually not algae but blue-green algae) in local reservoirs a year or so back. They were poisonous. Duckweed would be another, considerably less efficient, candidate. |
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Re: Stirling engines. The precision is what scares me, not the possibility of them blowing up. I like Stirling engines but the beauty of their design makes me feel inadequate. |
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we already have hemp ion and hemp diesel. It is just illegal to make under federal law. |
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