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Ethenol free gas

Gosh is this still continuing?

To get away from the internet, one needs to use this search: Scholarly articles for 10% ethanol gasoline and phase separation

The articles are written by techies and Ph.d types. In the articles, they discuss everything from how water gets into the pure gas to it's end affects on engines.


Fuel Phase Separation in Ethanol Blended Gasoline's
Courtesy of Scott Irwin
Did you know? In a 10% Ethanol Blend, it takes as little as 18 gallons of water in a 6,000 gallon tanks to cause Phase Separation. In a 2% blend it takes only 3.6 gallons to cause Phase Separation

What is "phase separation", and how do I deal with it?
If significant amounts of water are present in a fuel tank with gasoline that contains ethanol, the water will be drawn into the fuel until the saturation point is reached for the three-component mixture of water + gasoline + ethanol. Beyond this level of water, phase separation could cause most of the ethanol and water to separate from the bulk fuel and drop to the bottom of the tank, leaving gasoline with a significantly reduced level of ethanol in the upper phase. If the lower phase of water and ethanol is large enough to reach the fuel inlet, it could be pumped directly to the engine and cause significant problems. Even if the ethanol water phase at the bottom of the tank is not drawn into the fuel inlet, the reduced ethanol level of the fuel reduces the octane rating by as much as 3 octane numbers, which could result in engine problems.
Well-Worth Products, Inc.: Articles - Fuel Phase Separation in Ethanol Blended Gasoline's

Ethanol-Water Phase Separation White Paper
Samir Jain
Background
The use of ethanol as a fuel in the United States has significantly increased over the past decade.
Today, greater than 80% of all retail gas stations in the US blend gasoline with up to 10%
ethanol (E10). Ethanol is a renewable fuel, and has been highlighted by the national Renewable
Fuels Standard as a primary method of achieving the renewable fuels goal. Ethanol is also an
octane booster, and E10 fuels rely on the ethanol content to achieve octane levels.
Water Intrusion
Fuel is typically stored in underground storage tanks (UST) and it is common for water to find its
way into these tanks. Prior to the use of ethanol, water entering the tank would drop through the
fuel and find its way to the bottom of the tank were it could be detected and removed before it
would be picked up by the pumping system and delivered into a vehicle. Pure water is heavier, or
denser, than gasoline-based fuels. The following table shows the density of various fluids at
15°C (59°F):
Ethanol is a hydrophilic compound, which means it naturally attracts water. Therefore when
water enters a tank containing an ethanol blended fuel, the water will eventually be absorbed by
the ethanol. The amount of water that is absorbed in the fuel versus falling to the bottom is a
function of the rate of water flow into the tank along with the amount of mixing that occurs. Full
absorption usually requires some kind of mixing such as that provided during a fuel delivery to a
UST. Table 2 highlights many common reasons for water intrusion in an underground storage
tank, and the rate at which water flows into a tank.
http://nationalpetroleum.net/Ethanol-Water-Phase-Separation-facts.pdf

Journal of Petroleum Technology and Alternative Fuels Vol. 2(3), pp. 35-44, March 2011
Available online at Journal of Petroleum Technology and Alternative Fuels
©2011 Academic Journal
Full Length Research Paper
Physico-chemical properties of bio-ethanol/gasoline
blends and the qualitative effect of different blends on
gasoline quality and engine performance
Tangka J. K.1*, Berinyuy J. E.2, Tekounegnin3 and Okale A. N.3
Physico-chemical and operational properties of various gasoline bio-ethanol blends were evaluated.
Bio-ethanol was obtained through distillation from maize (Zea mays), sugar cane (Saccharum L), raffia
(Raffia vinefera) wine, and palm wine and then purified using a rotavapor. Engine trails involved
combinations of various ratios of gasoline/bio-ethanol as fuel in a small unmodified gasoline engine
connected to a dynamometer. The vapour pressure, octane number, flash point, specific gravity, and
energy density of various compositions of the blends were evaluated. Sugar cane gave the highest
yield of alcohol 97.99 g per kg of produce while the lowest amount of alcohol of 10.5 ml per kg of
produce was obtained from palm wine. Engine power decreased from 0.400 kW with 100% gasoline as
fuel to 0.108 kW with a gasoline ethanol ratio of 1: 10. The octane number increased from 93 at E10 to
106 at E90. The energy density decreased from 33.180 MJ/l at E10 to 23.600 MJ/l at E90. Other physical
observations suggest that to successfully run a gasoline engine with bio ethanol/gasoline blends some
modifications would have to be done on the engine, including advancing of ignition timing, provision of
air tight fuel conduit network, and modification of piston heads to improve pre-combustion fuel
homogenisation.

These are technical papers, not the usual stuff to read. Personally as I don't need to pass a course rather than read all of the above, I'll take their word for it. Doubters, feel free to embark on the most boring reading of their life.


MTBE
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MTBE is does not phase separate; however, it can pollute ground water so it is a no-no
 
Last edited:
Gosh is this still continuing?

To get away from the internet, one needs to use this search: Scholarly articles for 10% ethanol gasoline and phase separation

The articles are written by techies and Ph.d types. In the articles, they discuss everything from how water gets into the pure gas to it's end affects on engines.

There's no doubt that phase separation exists. My point is that it does not occur in sealed containers. No moisture, no phase separation.
 
As we have been discussing vehicle gas tanks which aren't sealed where did sealed containers come from?

The articles mention large tanks and judging by their size, the tanks are at a gas station, not the shipping depot which can have its own problems. The gas can be contaminated with water when we pump it into our vehicles, why would a sealed container matter? The cap and flap won't help as the gas is contaminated when we buy it.

If it wasn't for the EPA we'd be using MTBE which doesn't have these issues.
 
As we have been discussing vehicle gas tanks which aren't sealed where did sealed containers come from?

Have you read any of the posts above? Post #7:


These sky is falling scare tactics about phase separation are laughable. Sounds like it's written by a high school kid that's never left his mom's basement

1) NO ONE drives around with their gas cap off which would be the minimum required to allow significant moisture to enter and contaminate the gas. Cars since the 60s have had sealed or semi sealed gas caps that allow zero direct inflow of air or only when a slight vacuum is applied. They are not open like some older boats.

2) Supposedly, phase separation will cause the water laden ethanol to sink to the bottom of tank while the gas floats to the top. If this was true, the engine wouldn't start or run. How would it therefore become damaged?

3) Despite 30+ year presence of E10 in North America, the first 20 of which no attention was paid to the above 'issues', genuine real-life problems on cars have yet to surface.

In that connection, here's what 2 year old E10 looks like in a sealed gas tank.

This is a car forum. I don't leave any type of fuel in any small engine over the winter. They don't have sealed gas systems like cars which makes all the difference in the world. Here's a picture of the inside of my car's gas tank. The gas is two years old. It's had nothing but E10 since the mid-90s Do you see any water, phase separation or corrosion? :eyerole


View attachment 20052

If you want to argue that gas stations sell precontaminated gas, off you go, good luck.
 
If you would have read the scholarly articles, you would have noticed they consistently mentioned large tanks, ie. 6000 gallons. The point was the water is in the gas before you pump it.
As it is already present, there is nothing you can do at the consumer level to prevent it. At the end of the day, the reality is; we have two choices, accept it or ignore it.

If you want to debate them, write them and correct their errors.
 
If you would have read the scholarly articles, you would have noticed they consistently mentioned large tanks, ie. 6000 gallons. The point was the water is in the gas before you pump it.
As it is already present, there is nothing you can do at the consumer level to prevent it. At the end of the day, the reality is; we have two choices, accept it or ignore it.

If you want to debate them, write them and correct their errors.



Our Tech Line support always advises us to educate our customers on the advantages of Top Tier fuel AND purchasing their Top Tier from a high volume seller so as to minimize the contamination of fuel from their storage tanks. There is still a fair amount of driveability issues out there, and almost all of them are related to the E-10, winter oxygenated fuels, and carbon build up.
 

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