Sciencemadness Discussion Board - Extraction of ethanol from gasoline

Extraction of ethanol from gasoline

Elemental Phosphorus - 24-2-2017 at 07:50

Many people, me included, have trouble sourcing ethanol as a solvent. As you know, at least here in the US, ethanol is blended into gasoline as a money handout to big agribusiness. Therefore I would like to extract ethanol from gasoline, ideally from E85 gas. Yesterday, I ran an experiment using 10% ethanol gasoline. 3ml of water was added to 60ml of gas. The mixture was added to a separatory funnel and aqueous layer collected. The gasoline was dried over CaCl2 to render it usable. The water/ethanol layer was dried over anhydrous NaCl. Some of the cloudiness cleared, but the mixture remained somewhat cloudy. I think this is due to either the NaCl not being completely anhydrous. It seems unlikely that slightly water-soluble hydrocarbons from the gasoline would cause cloudiness, although these will definitely be present as an impurity. Over the weekend I will try to find time to distill this. Any input on cloudiness or a way to separate somewhat water-soluble hydrocarbons?

Also, I do not know whether or not a cosolvent is present, as that would make things much harder. I will also experiment with E85 when I can find it. (They don't sell it at the closest station to me)

Thanks for the input.

Dr.Bob - 24-2-2017 at 10:40

By cosolvent, do you mean one of the hundred plus chemicals in "pure" gasoline? The have all sorts of stuff in there. Also, CaCl forms complexes with ethanol, it is not a good drying agent for it.

If you want to bother trying this, start with E85, it is already 85% ethanol, and widely available. Then you will have to distill a few times, plus some other stuff to get anything approaching useful ethanol.

If you search, there are at least 3 or 4 older threads that have beat this subject to death, the simplest way is to just ferment your own, and distill it, even that will have traces of methanol and esters to remove by double distillation or a really good distillation system (with a good fractionating column).

Elemental Phosphorus - 24-2-2017 at 14:16

The ethanol/ water fraction was not dried with CaCl2. Also, by cosolvent I meant a non-hydrocarbon chemical used to facilitate the mixing of the ethanol and gasoline. I chose not to go down the fermentation route because I have heard the legality of that brought into question. I will buy E85 and use that. However, the purpose of my previous post was basically: are there any useful hydrocarbon-selective reactions that can be used to remove various water soluble hydrocarbons like toluenes, etc. (I say toluene because it could be particularly difficult to separate as it forms azeotropes with both ethanol, water, and a three-component azeotrope of all three). Maybe reaction with NaOH over MgSO4 then boil off hydrocarbon and hyrolyse the ethoxide, and distill off ethanol?

j_sum1 - 24-2-2017 at 21:41

My understanding is that gasoline mixtures are pretty much intractable. Isolating any one component is almost impossible.

Corrosive Joeseph - 25-2-2017 at 01:11

I find this very interesting, but like j_sum says, I would think

Quote: Originally posted by j_sum1

Isolating any one component is almost impossible.

or at least, VERY difficult......... But as always, I could be wrong. I do try not to be doh................

Pump gasoline/petrol is quite a soup of chemical compounds. This is the standard for my local brew.

http://transportpolicy.net/index.php?title=EU:_Fuels:_Diesel...

I would imagine a few of those hydrocarbons have some miniscule, slight solubility in water and who knows how many azeotropes are present and that's even before the water is added.

Alkanes, alkenes, alcohols, ethers, aromatics................ And some..........

I would still love to see this work though, and a quick google search is seems to suggest it might be possible.
I have an ongoing project happening at the moment pursuing non-polar solvents from my local 95RON involving a series of distillations. I did wonder about phase separation to get rid of the alcohols but didn't give it any more thought again until I seen this thread..................

Just for visuals............. 'Phase Separations in Ethanol-Gasoline'
https://www.youtube.com/watch?v=Wrb4pl03xCg

Don't forget your gas/petrol alreadyprobably has some fuel stabilizer(s) added to it already..........

Snippets -

http://www.lcbamarketing.com/phase_separation_in_ethanol_ble...

http://www.accessnorton.com/make-your-own-ethanol-free-gasol...

Some attachments -

Attachment: Ethanol-Water Phase Separation White Paper.pdf (230kB)
This file has been downloaded 1168 times

Attachment: Phase Separation.pdf (148kB)
This file has been downloaded 434 times

Attachment: Water Phase Separation in Oxygenated Gasoline.pdf (15kB)
This file has been downloaded 928 times

Please post some links/research/experiments. I would love to know how this goes and maybe someone knows more................

I'm guessing a few fractionations are going to be necessary to get anywhere near a pure enough product if it is possible.......... I ferment all my own ethanol and I would NEVER dream of ingesting anything that ever had gasoline/petrol in it. I don't drink alcohol myself but I guess I had to mention that. ..............

Hope this helps

/CJ

[Edited on 25-2-2017 by Corrosive Joeseph]

Elemental Phosphorus - 25-2-2017 at 05:15

Yes, as it turns out both water and ethanol form large numbers of azeotropes with hydrocarbons. Isolating any one hydrocarbon component would prove near impossible, but I am hoping to take advantage of the reaction of ethanol with NaOH to boil off hydrocarbons and then hydrolyse the ethoxide. Would magnesium sulfate be a suitable drying agent to drive the equilibrium toward ethoxide? Of course I would never drink ethanol purified from gasoline but it may make a suitable lab solvent.
The page you linked for fuel compositions is somewhat worrying to me because it shows that other alcohols are present. Therefore these would form alkoxides as well and I will have a lot of fractioning to do to separate methanol. Here is a PDF of azeotrope data:

http://biopent.uv.es/~roberto/Docencia2013/LQFI/P6/06_35_86....

[Edited on 25-2-2017 by Elemental Phosphorus]

Texium - 25-2-2017 at 08:22

I think you'd be better off just buying (or, if you're underage, getting someone to buy) some Everclear. It's just food grade azeotropic ethanol so it's probably the purest stuff you can get OTC and is not that expensive. Saves a lot of headaches and labor for sure.

Elemental Phosphorus - 25-2-2017 at 08:46

Well, yes but for a larger scale application this is the cheapest way. I happen to have free supply of waste vegetable oil and for making biodiesel this is the cheapest alcohol I can find. I will however, try to get some everclear. Also, I like how OTC a method using gasoline is if I can't find everclear.

Photos of it burning

Elemental Phosphorus - 25-2-2017 at 09:04

Here is a photo of it burning. The liquid burns with the characteristic blue of ethanol, not the orange of gasoline, but it smells different than either ethanol or gasoline. I didn't have a watchglass so this is a pipe endcap.

JJay - 25-2-2017 at 09:09

If you're making biodiesel, be really careful with mineral acids and bases on polyester carpet - one drop will produce shockingly enormous blobs of goo and destroy the carpet.

It would be best to keep them away from carpet entirely.

Elemental Phosphorus - 25-2-2017 at 12:55

Yeah I usually do all my experiments outside but today it was pouring rain. Looking at it, burning something in a metal vessel on a plastic carpet wasn't the smartest idea but I put it out right after the photo.

Corrosive Joeseph - 25-2-2017 at 15:54

Looks like you are SOL with the phase separation then.............

Failing that I guess multiple fractionations on E85 will probably yield a half decent solvent but it will always have traces of the other compounds in it.................. Not good if your solute reacts with any of them................

I still believe turbo yeast, sugar and dedicated copper still is the only way to go for OTC ethanol..............

You will have solvent on tap and it frees up glassware for other more interesting things

/CJ

Elemental Phosphorus - 26-2-2017 at 12:18

Here in the US I have heard distilling and fermenting your own alcohol requires an ATF license. What do you mean by SOL? I am not familiar with certain shorthand. Also, I forgot to mention that light hydrocarbons like methane, ethane, propane and butane burn blue, but do pentanes burn blue? If so, the burning test does not confirm that those are not present.

Aquakidney - 26-2-2017 at 15:30

You can ferment anything you want, but distilling ethanol requires a permit. There are two kinds, one for beverages and one for industrial/fuel use. Getting either one is a colossal pain in the neck and requires much paperwork, site inspections from BATF agents, posting expensive bonds, etc. Nevertheless, if you're discreet and don't try to sell it, nobody will notice or care.

The amount of methanol formed during fermentation will be almost nothing. Just discard the first few mL of distillate to be sure.

If federal crimes make you skittish, another option is to buy a few 1.75L jugs of cheap vodka and redistill it through a good fractionating column. That should get you close to 95% and the rest of the water can be removed by the procedures in Vogel's Handbook.

Oh, and SOL means "Shit Outta Luck".

Archenemy_6 - 26-2-2017 at 20:17

I purchased a 750ml bottle of 95% everclear a couple weeks ago it was right around $20 I think. I've only used it with my soxhlet extractor so far. The cheap vodka might be a good route if you can find it cheaper than the everclear and don't mind spending some time distilling it.

Elemental Phosphorus - 27-2-2017 at 13:33

So distilling your fermented product is not okay, but say filtering and then drying over anyhydrous MgSO4 is fine? The drying agent could then be regenerated to produce a cheap, relatively pure product maybe?

Texium - 27-2-2017 at 13:54

Look, the bottom line is that law enforcement is not going to care whether you actually distilled your ethanol or dehydrated it using a ludicrous amount of MgSO4, so if you're just squeamish about breaking the law, you'd be best off buying denatured alcohol or legal, taxed drinking alcohol.

Elemental Phosphorus - 27-2-2017 at 18:56

That is why I'll get back to the original thing. I will be able to conduct the extraction from gasoline soon. The price of E10 gas is about $2.30 per gallon where I live. Despite the available sources, I cannot see the harm in a gas extraction. For a solvent, purity is relatively important, but for biodiesel it should be fine and also leave me with gasoline for burner fuel. This altogether would leave me with a price of about ~$7 for a liter of ethanol, as well as lots of leftover fuel which would be suitable for use in vehicles as well if dried appropriately to remove dissolved water. I may just ferment and distill, but the original purpose of the thread was to talk about extraction from gasoline. So, if the crude ethanol was added to NaOH with a drying agent to drive the equilibrium toward ethoxide, would it yield ethoxide so lower boiling components could be separated? The comment about filtering a ferment and drying was stupid, but I also meant to say that there being a rule on distilling only being strange and an odd way for the government to regulate, that is if they really care.

[Edited on 28-2-2017 by Elemental Phosphorus]

JJay - 27-2-2017 at 19:36

Alcohol laws in the U.S. tend to be somewhat arbitrary. It is perfectly legal to produce a high-proof beverage without a distiller's license using non-distillation techniques such as this one: https://www.youtube.com/watch?v=gAqKvM7JHkw Yet distilling a sugar wash to produce a solvent for lab use is illegal.

Law enforcement is not going to care about the morality of your technique for concentrating ethanol; they only care about whether it is legal and if there is money involved. You can give your uncle enough wine to cause intoxication right before he gets into a car accident, killing a family of four, and be totally in the clear, legally speaking. With alcohol, they are only concerned with enforcing the letter of the law.

There are some circumstances under which you can distill denatured ethanol without a license, but if they can show that you intend to prepare a beverage with denatured ethanol, you may have some problems.

Praxichys - 28-2-2017 at 08:05

Yes, unfortunately distilling ethanol at all in the USA is illegal.

https://www.ttb.gov/spirits/home-distilling.shtml

Quote:

Within title 26 of the United States Code, section 5601 sets out criminal penalties for activities including the following. Offenses under this section are felonies that are punishable by up to 5 years in prison, a fine of up to $10,000, or both, for each offense.

5601(a)(1) – Possession of an unregistered still.
5601(a)(2) – Engaging in business as a distiller without filing an application and receiving notice of registration.
5601(a)(6) – Distilling on a prohibited premises. (Under 26 U.S.C. 5178(a)(1)(B), a distilled spirits plant may not be located in a residence or in sheds, yards, or enclosures connected to a residence.)
5601(a)(7) – Unlawful production or use of material fit for production of distilled spirits.
5601(a)(8) – Unlawful production of distilled spirits.
5601(a)(11) – Purchase, receipt, and/or processing of distilled spirits when the person who does so knows or has reasonable grounds to believe that Federal excise tax has not been paid on the spirits.
5601(a)(12) – Removal or concealment of distilled spirits on which tax has not been paid.

This includes re-distilling legally distilled spirits or fuel alcohol.

On top of this, many states also have laws against this. In Michigan where I live, anything under 8 liters is a civil infraction (like a traffic ticket), 8 to 80 liters is a 93-day misdemeanor, and over 80 liters is a 4-year felony. I imagine this would add onto the federal charges described above.

That said, I doubt law enforcement has the resources to be concerned with small private distillers. These laws have been on the books since prohibition and were designed to quench the huge incentive to make homebrew at the time. As long as the state isn't missing out on tax money and you're not endangering the public (i.e. you're not selling/distributing it/distilling in an apartment building) I doubt anyone will really care. Just don't go showing off your apparatus and methods to your friends and neighbors. All it takes is one cop with big ears looking for a promotion to initiate an investigation.

JJay - 28-2-2017 at 09:13

Quote: Originally posted by Praxichys

Yes, unfortunately distilling ethanol at all in the USA is illegal.

https://www.ttb.gov/spirits/home-distilling.shtml

Having researched this thoroughly, I can tell you that this is not the case.

https://www.law.cornell.edu/uscode/text/26/5273 specifically gives permission for distilling denatured alcohol. It is worth noting that a large body of additional regulations apply to "specially denatured" alcohol, which is discussed here: https://www.ttb.gov/industrial/sda.shtml

E85 belongs to the class of "completely denatured" ethanol mixtures, so it's generally legal to distill it without a permit as long as you aren't boiling off the denaturants into the atmosphere or trying to prepare a beverage. Note that if you're selling it, there are additional regulations, and you should of course keep a lab notebook and keep the ethanol from falling into the hands of people who might drink it and so forth. It is pretty easy to obtain a permit for distilling fuel alcohol if you want to make it yourself from natural sources, though.

[Edited on 28-2-2017 by JJay]

Praxichys - 28-2-2017 at 10:50

Yes, but denatured alcohol is not ethanol. It is a mixture, and as you mention, it is perfectly legal to distill. (Unless you're in Texas!

)

Distilling E85 or gasoline to obtain substantially pure ethanol (which is what the OP hopes to do) can be legally construed as "removing the denaturants" and is therefore illegal.

It may be straightforward to get a fuel alcohol permit, but you need to own specially zoned land to actually do it legally. Your fuel still will be inspected prior to its operation by a BATFE agent. Your premises will also be subject to random inspection and recordkeeping audits, as well as special taxation. It is not at all practical for the home chemist.

JJay - 28-2-2017 at 11:14

I haven't researched home fuel alcohol production thoroughly, but I do know that it is less regulated than spirit production. Most chemists want it to use ethanol as a reagent.

If you're distilling some denatured alcohol to remove water, that's generally legal. But doing it to prepare a nontoxic product is generally illegal.

I haven't reviewed the OP's plans thoroughly... it's clearly legal, in an appropriate location, to remove some of the non-ethanol components from E85 by distillation as long as the resulting product is still toxic or if it's distilled directly into a toxic mixture or consumed in a chemical reaction, etc. These components certainly have some value as fuel, so I assume you'd still want to keep them around. I should add that there is probably no good reason not to obtain a permit for your planned use, even though it might not be 100% legally necessary, depending on your recordkeeping and storage practices and so forth.

MrHomeScientist - 28-2-2017 at 11:34

From the discussion it sounds like distilling ethanol from gasoline is legal (being a mixture), but then if you take that same ethanol and redistill it for better purity it's now illegal?

Weird.

Lefaucheux10 - 28-2-2017 at 11:43

For better separation of ethanol from the gazolin why not use aqueous calcium chloride and then distill ethanol from the aqueous calcium chloride ethanol mixture ?

JJay - 28-2-2017 at 12:29

Quote: Originally posted by MrHomeScientist

From the discussion it sounds like distilling ethanol from gasoline is legal (being a mixture), but then if you take that same ethanol and redistill it for better purity it's now illegal?

Weird.

Haha. Yeah, pretty much, although it depends on exactly what you are doing. I've personally never distilled any gasoline, but I guess there are lots of interesting things in it....

Elemental Phosphorus - 1-3-2017 at 07:35

I am sorry if any of my posts have come across as rude or disrespectful. I do not mean any disrespect to anyone here. You all know more about chemistry than I do. I cannot see harm or a safety issue in extracting ethanol from gasoline however. If there was (and inform me if I missed something) I would not attempt it.

PirateDocBrown - 2-3-2017 at 09:10

I once contemplated extraction of ethanol from E-85 as well.

But I did a bit of research, and found some paint store alcohol that was at least 85% EtOH as well, but the remainder was water, methanol, ethyl acetate, and likely some bitrex.

Now, to get lab-usable EtOH, I reflux the stuff with some NaOH to hydrolyze the EtOAc, then add some dessicant (can't remember if I used CaCl2 or MgSO4), and did a simple distill, throwing out the lead fraction.

Excess water was soaked up with K2CO3.

There might be a trace of MeOH in it, but it's pure enough for almost anything I might use it for in the lab. I've even considered using it for synthesizing ethyl ether, as dimethyl ether and methyl ethyl ether would be lost to the gas phase.

If you want more pure EtOH, find some pure ethyl acetate and hydrolyze it all.