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Discussion Starter #1 (Edited)
Since there seems to be some interest in this I will post a couple pics of removing the ethanol form Egas.

I did this on a small (100mL) scale first. I added 80 ml of Egas to the graduated cylinder then 20 ml of Reverse Osmosis filtered water. (In all of my chemistry labs we get good results with RO water in place of distilled).
20170228_101835.jpg

I then transferred the mix to the flask and gave it a good shaking. and then transferred it back to the graduated cylinder and let it separate for a few minutes.
20170228_101905.jpg 20170228_101920.jpg

2 things to note here.
The "water" volume in the bottom has increased from 20 ml up to about 26.8 ml. And the over all volume has decreased from 100 ml down to about 92 ml
The increase is due to the ethanol leaving the Egas and dissolving into the water.
6.8/80*100= 8.5% increase. Which is a little shy of the "up too 10% ethanol" posted on the pump. But not too bad.
The 8 ml loss overall is due to 3 things. 1) Wetting loss, some of the mix sticks to the sides of the flask, 2) evaporation, it is gas after all, 3) density change, The alcohol molecules "pack" more tightly with water than they do with gasoline, and hence take up less space.

Next I attempted to up scale this process to 1000 ml
Same process, start with 800ml Egas
20170228_102301.jpg

Then add water to bring the volume up to 1000ml
20170228_102418.jpg

This time I tried to just mix the two in the graduated cylinder (didn't have a big flask handy, and didn't want to wash one, what a bum)
 

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Discussion Starter #3 (Edited)
Here the results of the upscale
View attachment 107265

After sitting for another couple minutes it came up to 240ml. this was a pretty big decrease from the first trial.
40/800*100=5%
This is quite a bit less than before, I think that a good vigorous shaking is pretty important if you want to get good removal. For larger scale use of this technique I would need a good sealing container that I can shake vigorously. A three liter soda bottle comes to mind.

Another factor that you need to consider is that ethanol has a significantly higher octane rating than most gasoline. It will vary depending on what you start with but generally speaking removing the ethanol is going to lower the octane rating by about 3 points. The gas companies get away with starting with low quality gas and then compensate by adding ethanol.

The basic Chemistry here is that Ethanol has a polar hydroxyl group (OH) attached to the end of its hydrocarbon chain. This makes it attract to water, which is also polar. Imagine a shoe box full of round magnets and glass marbles. After a little shaking the magnets will all stick together in a lump in the bottom of the box leaving pure marbles above. Same basic thing is happening here.
 

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I like to know what I'm getting also. I have this to check the gas.

https://www.amazon.com/Stens-750-760-Alcohol-Content-gasoline/dp/B001OK8Q6A/ref=sr_1_5?ie=UTF8&qid=1496932150&sr=8-5&keywords=ethanol+test+kit






I love experiments like this! This kind of stuff is what I show my boys. Thanks for the thread.
I've considered removing the ethanol, but that would also lower the octane of the fuel, since they use a lower grade gas and use the ethanol to raise the octane to the desired level.

https://www.fueleconomy.gov/feg/octane.shtml

Luckily I can drive 10 miles and buy non-ethanol gasoline.
 

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Why are you wanting to remove the alcohol from your gas if it lowers the octane rating?
One thing this does prove is that you do not want to get water in your gas, as it will pull the alcohol out and leave a big slug of the stuff sitting at the bottom of your tank, or worse, you start your bike after it's been sitting and separating and only run it a minute or two, now having a bowl full of almost pure alcohol sitting in the carb.

If this happens to a 2-stroke motor, it will seize upon start up. Has happened to me!
 

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Discussion Starter #6 (Edited)
Ok so I sat down and did the math. 87 octane with 10% etOH removed drops to 84.1 octane. 91 octane drops to 88.556 octane.

The formula is (starting octane - 11.3)/.9 = octane with 10% etOH removed.

So if you are going to do this for a TW I would recommend starting with at least 89 octane. This gives you 86.3 which should be fine for a low tech TW engine.
 

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Why are you wanting to remove the alcohol from your gas if it lowers the octane rating?
One thing this does prove is that you do not want to get water in your gas, as it will pull the alcohol out and leave a big slug of the stuff sitting at the bottom of your tank, or worse, you start your bike after it's been sitting and separating and only run it a minute or two, now having a bowl full of almost pure alcohol sitting in the carb.

If this happens to a 2-stroke motor, it will seize upon start up. Has happened to me!
Thank you for saying that. A lot of people are hung up on engines blowing themselves up because the operator used gas with ethanol in it.

Ethanol sucks the moisture out of the air. It will retain moisture up to a certain amount, then it suddenly becomes heavier than the gasoline it's suspended in and it sinks....as you say, to the bottom of the tank. Be it a fuel pickup or gravity, the bottom of the tank is where fuel is drawn from, resulting in whatever it is trying to run on 'pure' ethanol.

Moisture dropout can happen by getting actual water in your gas, but also through it absorbing moisture out of the air. If your gas is in a full, sealed container, there's essentially no issue. 1/4 of a tank/can of gas and 3/4 of a tank/can of air...that's a lot of air to suck moisture out of.

Keep your tanks and cans full if they're going to be sitting for more than a few weeks.

No, I don't want ethanol in my gas...unfortunately, it's there, so it's important to recognize what causes the actual problem with it. (Okay, aside from the 10% loss in power....hehe)
 

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Why are you wanting to remove the alcohol from your gas if it lowers the octane rating?
The primary reason you want to get the ethanol out of there is the water attracting junk it leaves in your tank

The secondary reason you want to get that crap out of your fuel is because it is less efficient, despite the octane rating, and will result in lower miles to the gallon – and let’s face it, we T’dubbers don’t have much room for that

The third (and least) reason, is that that it eats through a lot of components commonly used in older fuel delivery systems.

Some of these things are so small they’re almost insignificant, and it’s only when ethanol fuel is left sitting for a significant amount of time that they become evident. Japanese petrol (for instance) is already reputed to be contaminated with 5% or more of water content, so they allow for that in the manufacturing process – but it’s the ethanol that’s the enemy, especially in seldom used smaller engines.

In order to cure this, either you start decanting your fuel – or you fire your politicians, change your agricultural policies, and start buying 250cc strimmers.

If Trump is serious about leaving the Paris Accord regarding global warming, you may yet be in with a chance ……



(This has been a Party Political broadcast on behalf of the Conservative Party. Offer is subject to availability, terms and conditions may apply. If the offer is not available in your country, please contact your local politician.)
 

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Not to start an argument but I drive a 1947 Ford with a 1951 mercury motor. I have never had a problem with ethanol and we have the 10%. I never fill the tank after a run,just park it with what ever is in the tank when I get home. The same with a 1986 Harley. I had not started it for several months until yesterday. It started with no problem with the old gas. Same with lawn mowers and chain saws. My TW set for two months while I was gone and it started right up after charging a dead battery. But I have a generator that will only run with the choke half closed. It had been over two years since I tried to run it. Having said all this I prefer gas without ethanol.
 
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