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Author Topic: Ethanol Separating Out? Back to Topics
Banjoe

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Message Posted: Dec 20, 2012 9:40:03 AM

Heard an interesting fact/old wives' tale/myth that ethanol will separate out of a gasoline blend if left for an undefined length of time.

I was thinking if this is true, maybe this is why some folks are seeing engine damage while most are happily going about their days for years on end.

Any truth behind this separation theory?
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E-Squirrel
Champion Author Orange County

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Message Posted: Dec 28, 2012 5:55:52 PM

Separation can occur any time that enough water contaminates the fuel. Note that ANY water mixed with pure gasoline, immediately separates completely.

Adding ethanol to gasoline actually increases the tolerance to small quantities of water contaminating gasoline.

Whether or not you have this problem depends entirely on whether or not you have a water contamination issue (from condensation, or other source).

If you didn't with pure gasoline, its very unlikely that you will with ethanol added; if you currently do have a water contamination problem using pure gasoline, you MIGHT have some problem with ethanol blended fuel, but perhaps not.

Its always best to understand the facts, rather than paying attention to rumors.
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Hannie59
All-Star Author Appleton

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Message Posted: Dec 26, 2012 9:45:46 AM

And one simple fact is that phase seperation does not occur in vehicles, as they are in motion too much of the time. This causes constant blending of the fuel within the fuel system itself. Cannot happen in a vehicle unless idle for at least 2 months, but not even likely unless it's longer that that.
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SoylentGrain
Champion Author Illinois

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Message Posted: Dec 25, 2012 10:00:08 AM

"I even did a test for E10 in a open jar and after two years it completely evaporated with no phase separation. "

That implies the ethanol water fraction has a higher vapor presser than some components of gasoline. Which means, if water can enter the system to mix with ethanol, it can leave as well.
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goldseeker
Champion Author West Virginia

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Message Posted: Dec 25, 2012 1:54:15 AM

I even did a test for E10 in a open jar and after two years it completely evaporated with no phase separation.
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Banjoe
Champion Author Winnipeg

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Message Posted: Dec 23, 2012 8:35:42 AM

So no water, no separation. Thanks for nailing this as a myth, folks.
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goldseeker
Champion Author West Virginia

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Message Posted: Dec 23, 2012 8:17:23 AM

I have had ethanol fuels set for over a year with no separation.

It is indeed an old wives tale.
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SoylentGrain
Champion Author Illinois

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Message Posted: Dec 22, 2012 8:45:50 AM

" The story I heard was that leaving a mixture for some unspecified time allowed the two to separate within the container. "

What you have been told is chemically impossible. If ethanol separates out from gasoline, it is because water or some other polar molecule has been added to the fuel tank.

Ethanol is a bipolar molecule. It is soluble in both gasoline (nonpolar) and water (polar). Up to the saturation point, water is soluble in a mixture of ethanol and gasoline. When the saturation point is reached, the water displaces the gasoline from the ethanol and a blend of water and ethanol separate from the gasoline. That's called phase separation.

[Edited by: SoylentGrain at 12/22/2012 8:48:44 AM EST]
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Banjoe
Champion Author Winnipeg

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Message Posted: Dec 22, 2012 8:02:07 AM

SoylentGrain - I'm wasn't looking at a water-caused separation but rather an ethanol / gasoline separation. The story I heard was that leaving a mixture for some unspecified time allowed the two to separate within the container.

If this actually happens, then perhaps the problems that some folks are experiencing are caused by burning straight ethanol instead of properly mixed solutions.

This theory is based on the mixture actually separating which I haven't heard as a possibility. I'm now leaning to myth rather than fact.
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SoylentGrain
Champion Author Illinois

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Message Posted: Dec 21, 2012 10:21:01 AM

"My thought is that if separation can occur over a short (or even geologic) time, could the resulting products be causing the engine issues that some people are reporting?"

It's not an issue, because, phase separation does not occur over a short period of time, since the fuel tank is essentially sealed from the outside atmosphere. Basically, the only way to instill enough water to produce phases separation with fuel containing ethanol is to physically add it to the fuel tank.

"Another question - if there is separation, can the mixture be reconsituted? "

Yes. But,if I recall correctly, the amount of gasoline would be considerable. If you have that much water in the tank to create phase separation in the first place, it's too much water. You would probably nitice the engine running rough, if it runs at all.

The reality is water in regular gasoline is going to cause problems more than the same amount of water in gasoline and ethanol. That is because almost 100% of the water added to gasoline goes right to the bottom of the tank. When that happens, the engine stops in it's tracks. Won't even turn over.

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Banjoe
Champion Author Winnipeg

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Message Posted: Dec 21, 2012 9:17:47 AM

From what I'm reading from you wise guys, there seems to be validity in the separation theory. I've been using a methanol blend for many years and have never experienced gasline icing issues like the old days when we had to add alcohol to take care of the inevitable water in the gas.

My thought is that if separation can occur over a short (or even geologic) time, could the resulting products be causing the engine issues that some people are reporting?

Another question - if there is separation, can the mixture be reconsituted?
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krzysiek_ck
Champion Author Illinois

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Message Posted: Dec 21, 2012 8:19:34 AM

easydriver11 wrote: "While food prices rocket and people around the world are starving we put corn in our gas tank. These environmental idiots should have to pay our food cost increases and give up their food for the starving people around the world"

Feel free to provide some proof to your statement.
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easydriver11
Champion Author Cape Coral

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Message Posted: Dec 21, 2012 6:34:23 AM

While food prices rocket and people around the world are starving we put corn in our gas tank. These environmental idiots should have to pay our food cost increases and give up their food for the starving people around the world
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krzysiek_ck
Champion Author Illinois

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Message Posted: Dec 20, 2012 9:28:09 PM

In short, Minnesota Department of Commerce believes that Ethanol blended gasoline handles water much better than E0, where more Ethanol is better.

I also find this interesting.

"Q: Is water contamination in gasoline a big problem in Minnesota?
A: No. The vast majority of stations in the state will never experience any water contamination in their product."

or

"Ethanol acts very much like the Isopropynol some people add to their vehicles' gas tanks in the winter. It absorbs the water and prevents gas line freeze. In small amounts, water in a gasoline/ethanol blend will not affect a car's performance."
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reb4
Champion Author Chicago

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Message Posted: Dec 20, 2012 8:08:56 PM

Here is an interesting Page from Minnesota Government site I found on the subject, I would presume somewhat reliable..

"Q: If ethanol absorbs water, how can you have water contamination in a gasoline/ethanol blend?

A: A gasoline/ethanol blend can absorb a certain amount of water. In general, the greater the percentage of ethanol in the blend, the larger the amount of water the blend will hold. Also, the higher the temperature, the greater amount of water the blend will hold. A blend that contains the maximum amount of water it can absorb for that temperature and percentage of ethanol is saturated.

If a saturated blend drops in either temperature or percentage of ethanol, the water will start to precipitate (fall) out of the solution and settle at the bottom of the tank. This water will be mixed with ethanol since ethanol bonds more easily with water than gasoline. The gasoline mixture at the top will still be saturated. It will continue to precipitate out a water/ethanol mixture as the percentage of ethanol drops until there is either no more water in the gasoline, or another saturation point is reached (if the temperature is rising at the same time, for example). This is what is referred to as a phase separation. A phase separation can occur in a storage tank or in a vehicle's gas tank. As soon as water/ethanol begins to precipitate out, an in-ground tank's sensors will be able to detect its presence and signal the operator that there is a problem.

Q: What happens if people buy phase-separated gasoline?
A: If a phase separation occurs in a station's storage tank, the customer may get either gas/water/ethanol, gas/ethanol, or water/ethanol depending on the degree of separation, and the height of the water/ethanol phase in relation to the discharge pipe leading from the tank to the dispensers.

Q: Will everyone who buys phase-separated gasoline experience car problems?
A: Fortunately, no. Very few people usually experience problems. Many people buying a water-saturated product will still have some unsaturated gasoline/ethanol blend in their tanks. Most people's gas tanks are often warmer than stations' in-ground storage tanks during the spring, summer, and fall months. This means that a blend which is saturated in the ground will no longer be saturated in the car's tank. In a few rare cases the water/ethanol phase in a contaminated tank may reach the level of the tank's discharge pipe. Usually a phase separation is detected and corrected long before this is the case. Any customer who purchases part of the water/ethanol phase will experience difficulties immediately.

Q: What should I do if I suspect I have purchased water contaminated gas?
A: Drain your tank and change your fuel filter. This is extremely important for carbureted vehicles since water can damage the carburetor. If the gasoline appears cloudy, or if it separates into visible layers, it probably contains water. Contact the station operator. (A canceled check or receipt to show when you purchased the gasoline is useful.) Most operators will be happy to work with you if the contaminated product came from their station."

I personally do not leave gasoline in my lawnmower, or snowblower over the off season...



[Edited by: reb4 at 12/20/2012 8:12:10 PM EST]
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krzysiek_ck
Champion Author Illinois

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Message Posted: Dec 20, 2012 11:12:51 AM

I have never drained my snow blower or lawn mower. I also have a car that I park in the garage over winter with E10 in it. I have never had any problems with "Ethanol separation".
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SilverStreaker
Champion Author Twin Cities

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Message Posted: Dec 20, 2012 10:59:50 AM

Banjoe, I think "old wives' tale/myth" is more appropriate. I've never experienced this. I've stored E10 over the winter many times with no indication of separation. By "undefined length of time", are they talking about geologic time?
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