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# Removal of ethanol from gasoline7

## Removal of ethanol from gasoline

(OP)
I have seen where mixing water with E10 pump gasoline will then allow the water/ethanol mixture to separate from the gasoline. This is stated to be necessary for preservation of older (collector) vehicle fuel systems that suffer many ills from the new gasoline E10 or E15 fuels. I understand this will reduce octane rating somewhat. A few relevant questions for the fuels experts:

1. Is the water mix/separation method effective?

2. What are the disadvantages here, with respect to use in older IC engines? Understanding that labor and costs to end up with less fuel and less total heat value is an obvious result.

3. What steps may be taken to correct or adjust properties of the separated (ethanol removed) gasoline to be more compatible with old engine fuel systems?

4. Is heat distillation an option here (with proper safety precautions), and how would that be done? I remember in public high school years ago (1960s) the chemistry class ran several fractional distillations (6 teams of 5 students each) of pump gasoline in the chemistry classroom, Bunsen burners under glass containers, condensing the distillate with glass water cooled heat exchangers, all six distillations running simultaneously in a classroom with 30 students. I'll bet that is not done these days!

### RE: Removal of ethanol from gasoline

I think gas boils around the same temp as ethanol. Maybe you could add water vapor after that to make the ethanol vapors seperate from the gasoline?

"Formal education is a weapon, whose effect depends on who holds it in his hands and at whom it is aimed." ~ Joseph Stalin

### RE: Removal of ethanol from gasoline

A gasoline/ethanol/water phase diagram (there's one in patent EP 2085460) shows how it splits. Line 1, line 2 etc. show compositions in equilibrium with each other, so decide how much water you want to add (inside the phase split area). You need to add enough water to get the ethanol down to your required spec, but not so much that you dissolve excess water in the gasoline. The points on either end of the line tell you how much water and ethanol dissolve in the gasoline phase, and how much gasoline in the ethanol/water. Mass balance to determine how much of each.

Ethanol's normal boiling point is 78 deg C. Gasoline is a complex mixture of compnents with different boiling points, so it has a vaporisatoin curve that starts about 35 deg C and finishes about 200 deg C. To complicate things, ethanol interacts with gasoline (hence the odd effects on RVP and the phase split). Yes, you can distill out ethanol by removing lighter than ethanol, then heavier than ethanol, then recombining, but the economics of doing so are not in your favour. As you note, this stuff is very dangerous and unforgiving even if you know exactly what you are doing.

Matt

### RE: Removal of ethanol from gasoline

Recommend you post this question to the chemical engineering group - other topics.

### RE: Removal of ethanol from gasoline

I'll be impressed if you come up with a process that is cost-effective to the point of being cheaper than just finding and paying for the nearest available non-ethanal treated gasoline. I did notice that many stations in the upper midwest where I was travelling last month had special nozzles for "power equipment only", which were ethanol free (but still unleaded with decent octane).

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

### RE: Removal of ethanol from gasoline

IMHO, hemi has the point. It is very probably cheaper to find a satisfactory gasoline free of ethanol than to remove same from ordinary gasoline AND adjust the resultant solvent mixture to a reasonable fuel.

(OP)

### RE: Removal of ethanol from gasoline

3

#### Quote (tbuelna)

All gasoline sold in the US now contains at least 10% ethanol to reduce emissions buy votes in Iowa.

fixed that for you.

Cheers

Greg Locock

New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

### RE: Removal of ethanol from gasoline

For my own entertainment, I looked up the data on ethanol interaction with some common gasoline components. There are all sorts of minimum boiling azeotropes, so my simplistic proposal of taking a heart cut of ethanol was over-optimistic. Still physically possible, if you threw enough columns and presssure swings at it but the design would be hard.

If ethanol interacts enough to form azeotropes, I'd be surprised if it freezes out cleanly. I couldn't find any SLE data though. Water and phase separation still wins my bet for safest and easiest.

Matt

### RE: Removal of ethanol from gasoline

(OP)
tbuelna: (Aerospace)18 Aug 15 05:15 "All gasoline sold in the US now contains at least 10% ethanol"

That is not true. Gasoline with no ethanol is sold in every state of the USA. Often not convenient to buy it, but it can be bought.

### RE: Removal of ethanol from gasoline

140 airpower:

Have I ever freeze distilled gasoline? No.

But I have done it with glycol/water mixes, as you mentioned, and it also works for hydrazines (though these too are water soluble, azeotropic mixtures). And, I have done freeze purification on heavier hydrocarbons...so it could work...in theory. Just like distillation would work...in theory. The only difference, as I pointed out, is that a frozen lump of hydrocarbon slush is less likely to ignite than boiling liquid.

I once ran tests using a Chevy van as a stationary power source, and we were a bit surprised when the vapor recovery system blocked up, resulting in fuel vapor spewing from the gas cap vent. Underbody temp's. near the tank had reached upwards of 180 F. NOT fun. They keep people away from refineries for good reason.

### RE: Removal of ethanol from gasoline

http://nationalpetroleum.net/Ethanol-Water-Phase-S...

This source suggests that phase separation may be a viable process. Regarding point 2, as others have noted, the processed fuel will be lacking some anti-knock qualities due to the removal of the ethanol. Some of the "miracle in a bottle" additives may or may not be worth looking into. I believe many of the so-called octane boosters are ethanol based. Doping with avgas might work. I cannot speak to the other points, having no knowledge of them.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

### RE: Removal of ethanol from gasoline

#### Quote:

="tbuelna" There should be no problem using pump gas with up to 10% ethanol in any vehicle.

Exactly true, PROVIDED old-style rubber in the fuel system is replaced with ethanol-compatible parts.

I drive a '52 Ford with the flathead V8, and have for the past 12 years. The only concessions to modern fuel I've had to make are hardened valve seats and an electric fuel pump. I've put many miles on it with absolutely no adverse effects, running on E-10 100% of the time.

On one of the forums for old Fords I frequent, there are a couple of guys who "wash" the ethanol out of their gas (they also add "lead substitute" to the resulting fuel). They have not provided any real feedback on the success of their efforts, for reasons I can only guess. For every one of these guys washing their gas, there are ten thousand running E-10 with no ill effects (subject to the caveats above). IMO whoever is telling the OP that straight gas is needed has no basis in fact for the statement. This subject ranks right up there with the "OMG they took zinc out of oil".

### RE: Removal of ethanol from gasoline

2
Oh, now we're backing up to the topic of whether ethanol-free fuel is necessary.

#### Quote (RossABQ)

I've put many miles on it with absolutely no adverse effects, running on E-10 100% of the time.

While it's hard to collect information from any one source, I have noticed a trend among the many anecdotes available that infrequently used machines have the most problems. Also fuel systems made of elastomers that are not rated for ethanol. Or you could ask my favorite marina in Canada about the incredible increase in fuel system repairs for their American customers that began when ethanol was added to fuel in the US. Their parts wall is covered with fuel hoses and squeeze bulbs and the like and they sell them frequently. The real-world difference doesn't appear to affect every single case, but on a whole the evidence of the difference is overwhelming.

For the OP, I propose to simply buy the fuel from VP Racing. They will ship it to you by the barrel or 5gal can.

David

### RE: Removal of ethanol from gasoline

Why don't you try it? From what I've read, about 2 cups of distilled water per 5 gallons of gas should be enough water to separate the ethanol. Mix it then let it settle until the remaining water and water/ethanol is at the bottom of the tank and then drain if out. As for your questions.
1. Yes
2. Lower octane and you will never know what you're doing to the other chemicals/additives in the fuel. You also end up with contaminated water.
3. No idea. You didn't say what vehicle. Also, gasoline contains a whole bunch of chemicals depending on where it's sourced and who it's sourced from and one of those could possibly have adverse effects on your vehicle.
4. I think it's already been established that this would be dangerous and difficult to do.

The easier solution is to either buy fuel without ethanol or drain the fuel when storing the vehicle or before the fuel is more than say 1 month or 2 months old if you're so worried about it.

### RE: Removal of ethanol from gasoline

I buy a $5 bottle of the$20/gal stuff from the local hardware store (Ethanol free) and then use it to clear the regular E10 gasoline out of my chainsaw, string trimmer, leaf blower, and generator before I put them away for longer periods of storage (month+). Without this step, my chainsaw would be inoperable coming out of storage. The weed whacker seems to tolerate the E10 well enough over the winter. Never risked it in the generator.

### RE: Removal of ethanol from gasoline

The OP asked about gasoline without ethanol for use in a historic vehicle that might have fuel system components (seals, hoses, etc) that would not be compatible with long term exposure to ethanol. While as some suggested it is possible to purchase ethanol-free race gasoline, this gasoline is also very expensive, is only available from a few retailers, and is not actually legal for use on public highways. It would be far easier and less costly to simply replace a few fuel system components with ones that are compatible with gasoline containing 10% ethanol.

### RE: Removal of ethanol from gasoline

(OP)
---tbuelna "It would be far easier and less costly to simply replace a few fuel system components with ones that are compatible with gasoline containing 10% ethanol."

I don'tknow what planet you are from, but that statement certianly does not apply here on earth. Maybe $100 for each replacement job? Far easier? Who does this work, and can find the right parts, etc. Please let us know if there is anyone doing these fuel conversions at a low cost, or, for that matter, anyone offering this service at all? I have 3 pressure washers, three tractors, 2 lawnmowers, 2 chain saws, 2 emergency generators, two motorcycles, all built in the last century, who doI call to get the far easier and less costly to replacment fuel system components with ones that are compatible with gasoline containing 10% ethanol? Those machines are not the most important in my mind, but my backup outboard motor is. I bought a new Suzuki ultra low emissions 4 stroke outboard only for backup on my boat, the boat has only one main engine, and being stranded on the river is not an option in my mind. Having reliable backup power is manditory on the Delaware (remember the tour duck boat that was run over by a tug/barge and killed a few people recently?). The Suzuki was hard to start on E10, and when I went looking on marine forums, I found that the engine is very good with non-ethanol gas, and universally hard to start with ethanol blend. Many owners chimed in about the starting problems on E10. There is a jet kit conversion available, to richen the mixture, and then the engine starts OK with ethanol gas, but finding and installing this stuff voids the warrantee, so I want to use real gasoline. I use the outboard about 1 hour per year, same as most of the other engine driven equipment listed above. ### RE: Removal of ethanol from gasoline I certainly don't dismiss the anecdotes about starting issues with E10, but I don't see the mechanism where air/fuel ratio is playing a role. Perhaps vapour pressure is the issue, but that could be investigated scientifically. "Schiefgehen wird, was schiefgehen kann" - das Murphygesetz ### RE: Removal of ethanol from gasoline In California gasohol (E10) has been around since the late 1970s/early 1980s. I used it indiscriminately in my old 1960s cars without problems, but it wasn't a steady diet. I just bought the stuff whenever stations that carried it had lower prices. It also helped old cars pass smog tests. "....I have 3 pressure washers, three tractors, 2 lawnmowers, 2 chain saws, 2 emergency generators, two motorcycles, all built in the last century, who doI call to get the far easier and less costly to replacment fuel system components with ones that are compatible with gasoline containing 10% ethanol?..." Fred, All of these engines are alcohol intolerant? It looks like you are going to be doing a LOT of fuel washing and hazardous waste water disposal or paying a lot for illegal fuel. ### RE: Removal of ethanol from gasoline I thought the idea was to drink the "hazardous waste". je suis charlie ### RE: Removal of ethanol from gasoline tbuelna "It would be far easier and less costly to simply replace a few fuel system components with ones that are compatible with gasoline containing 10% ethanol. " Perhaps at an OEM level it is easy and cheap to substitute a different material on the production line for a current vehicle, but when one is dealing with a vintage vehicle for which replacement parts - of ANY type, ethanol-compatible or not - are unobtainium, it changes from "far easier and less costly" to "nigh-on impossible". Hoses and O-rings and the like are easy, but the tough parts are the innards of fuel pumps, sending units, shut-off valves (that are designed specific for the fuel tank on the vehicle, so substituting something else is not easy), carburetor floats and needles and seats that are specific to the carburetor, etc. Locally (Ontario, Canada) Shell V-power 91 is ethanol-free, so that's what I have been using in the vintage and less-used vehicles. ### RE: Removal of ethanol from gasoline #### Quote (FredRosse) I don'tknow what planet you are from, but that statement certianly does not apply here on earth. Maybe$100 for each replacement job? Far easier? Who does this work, and can find the right parts, etc. Please let us know if there is anyone doing these fuel conversions at a low cost, or, for that matter, anyone offering this service at all?

Every vintage vehicle engine I have seen used very few elastomeric components in the fuel system. All the gaskets were metal or fiber. The only rubber components I can think of were fuel hoses or the fuel pump diaphragm. Ethanol compatible fuel hose is readily available at any auto parts store. And making a replacement fuel pump diaphragm from a suitable piece of ethanol compatible rubber sheet does not seem like a huge fabricating challenge.

### RE: Removal of ethanol from gasoline

(OP)
140Airpower - "Fred, All of these engines are alcohol intolerant?"

I do not know, but several have started to have problems which point to the typical ethanol issues so often cited. This comment has nothing to do with the original posted questions.

"It looks like you are going to be doing a LOT of fuel washing and hazardous waste water disposal or paying a lot for illegal fuel."

ANS; That depends on if I choose to wash the fuel. Illegal Fuel??? what do you mean here? Maybe for highway use, but that is not anything I have listed as the last century's machinery? Again, this comment has nothing to do with the original posted questions.

tbuelna - "Every vintage vehicle engine I have seen used very few elastomeric components in the fuel system. All the gaskets were metal or fiber. The only rubber components I can think of were fuel hoses or the fuel pump diaphragm. Ethanol compatible fuel hose is readily available at any auto parts store. And making a replacement fuel pump diaphragm from a suitable piece of ethanol compatible rubber sheet does not seem like a huge fabricating challenge."

ANS; OK, very interesting, a comment that skirts the question, I know all this already, and I note that Carb diaphragms, and many others, are almost never just flat sheet material, and next to impossible to find after the E10 has destroyed them. As BrianPeterson states ..."when one is dealing with a vintage vehicle for which replacement parts - of ANY type, ethanol-compatible or not - are unobtainium, it changes from "far easier and less costly" to "nigh-on impossible". But the stated question is "Who does this work, and can find the right parts, etc. Please let us know if there is anyone doing these fuel conversions at a low cost, or, for that matter, anyone offering this service at all?"

### RE: Removal of ethanol from gasoline

Hello,

I posted on August 17th about availability of ethanol free fuel near me in Atlanta. Well, my brother in law went to that same station yesterday and not only did they stop selling ethanol free gas, they switched those pumps to E70 (or some other flex fuel mix). Oh well.

For those of you who take on the challenge of removing the ethanol and have octane concerns, there is a product called "Race Gas" that is a concentrate to raise octane.

http://race-gas.com/

I don't know how well it works, but it's an option.

Kyle

### RE: Removal of ethanol from gasoline

Fred, "illegal fuel" just means that surely race gas is illegal except "off highway" at all times. Washed fuel with removed emissions reducing components (ethanol) would probably be considered illegal and there is a chance that any fuel not available in your area may be illegal in your area... -not that anybody is monitoring any of this.

### RE: Removal of ethanol from gasoline

There's an app for that http://pure-gas.org/

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

### RE: Removal of ethanol from gasoline

As the fuel ages, it tends to destroy the hoses and seals, E10 or not. Use this Link to stabilize fuels for up to 2 years. Other brands may work just as well, but this is the only thing I have ever used. I use it in all seasonal equipment and small generators.

### RE: Removal of ethanol from gasoline

Anecdotally, I have four 1955-99 vehicles, as well as a snow blower, rototiller, two lawn mowers, two chainsaws, weedwhacker, pressure washer, all pre-1999 engines. None of them have ever had problems I could trace specifically to E10 fuel. One 1955 Studebaker pickup had the original fuel pump, fuel lines and carburetor. I'd drive it in the summer and fall, park it over the winter and drive it out again in the spring with never any trouble. At the end, it was seeing exhaust valve seat and face wear but that was lack of tetraethyl lead, not presence of ethanol.

Want to make a petroleum chemist consider changing professions? Just tell him how you always add Stabil/Sea Foam/Marvel Mystery Oil/STP/Wynn's/diesel fuel/whatever-snake-oil to your gas tank or crankcase every fillup.

One such 30-year-Chevron-veteran told me, "Those marketing shysters buy their base stocks from us and re-label it and sell it for several dollars per pint. If it was a good thing, we could add it ourselves for less than a penny. Why is it so many car owners think they're a better petroleum engineer than I am?

jack vines

### RE: Removal of ethanol from gasoline

Have a look at this, just stumbled on it: www.ethanil.co.uk
Dirk

### RE: Removal of ethanol from gasoline

Stored fuel used to wreck my chainsaws. I started adding fuel stabilizer to my stored fuel and running the chainsaw completely empty prior to each storage. It solved my problems completely. Not all that practical with a vehicle though.

Fuel system components in vintage cars vary hugely from brand to brand, model to model and year to year. I can imagine some vintage cars having problems with E10, particularly on long storage between runs. But others will be totally fine.

I converted my vintage car to electric. It no longer has fuel system problems!

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