‘Washing’ ethanol out of mogas

The GAfuels Blog is written by two private pilots concerned about the future availability of fuels for piston-engine aircraft: Dean Billing, Sisters, Ore., an expert on autogas and ethanol, and Kent Misegades, Cary, N.C., an aerospace engineer and aviation journalist.

The process of separating ethanol out of unleaded auto fuel is a much discussed topic on many aviation forums, blogs and media articles.  In fact, there are now commercial enterprises that are offering ethanol “washers” so you can remove ethanol from gasoline.  It does strike me as rather odd that so many people spend so much effort on the process, and try to accommodate ethanol blended gasoline in their lives when they could be putting that effort and energy into getting ethanol blending prohibited in premium unleaded gasoline so it would be widely available for everyone who needs it … and there are an awful lot of people who need it. Just look at the nearly 3,000 comments on our petition to the EPA.  If you have not signed this yet, please do, and pass the word on.

Anyway, here are a few things that a pilot should consider if they are contemplating “washing” ethanol out of unleaded auto fuel that is blended with ethanol, usually at the 10% level, commonly known as E10.  If you do this, you cannot use the resultant “fuel” in any TC’d aircraft, even if you have a Mogas STC, nor any S-LSA aircraft, because there is no way to assure that resultant “fuel” is ASTM D4814 compliant, as it most assuredly isn’t because it is something you created, not something that was delivered as finished legal gasoline.

That leaves those owners of airplanes that are amateur built or ultralights to contemplate using this unknown fuel.  You can actually legally use this fuel if you have a placard at the fuel tank for it, since you are the “manufacturer” of the airplane.  You just need to accurately describe it on the placard.

So what is this “fuel”?  How will you describe it on the placard? This is what the director of the Division of Air Resources, New York State Department of Environmental Conservation said in his comments on the E15 waiver:

“E10 is not simply ethanol added to finished gasoline. Since most gasoline at retail contains ethanol, the industry factors the addition of ethanol into the formulation of the petroleum-based portion of the final blend. The chemical properties of ethanol and its dilution impact allow refiners to produce a petroleum-based blendstock which when combined with a specified amount of ethanol (or other oxygenate) results in a final blend with the desired legal and market properties. The petroleum-based blendstock, in most cases, would not qualify as gasoline or be legal to sell as gasoline. For RFG this blendstock is RBOB. For conventional gasoline it is CBOB, and for California RFG it is CaRBOB.”

Of course you don’t know what kind of fuel BOB actually is, and you don’t know how “washing” ethanol out of it has changed it, so I suggest you placard your homebuilt for “Unknown Octane Swamp Gas (UOSG)”, because that is as good a guess as anything.  And by the way, what do you plan on doing with the water-ethanol residue?  Be advised that whatever it is, it is considered a hazardous material in most of the U.S.  You might want to contact your state Department of Environmental Quality about how to dispose of it properly.

Now, is all of this really worth the effort?  Or would your time be better spent getting your state legislature or the EPA to prohibit the blending of ethanol in premium unleaded gasoline so that everyone who needs ethanol free fuel has it.  You aren’t alone, agitate!

Submitted by Dean Billing


  1. says

    Pete – Your contact at the Chevron refinery is completely wrong. As of today Florida is NOT a mandatory E10 state. It won’t be until 1 January 2011. There is NO mandatory federal E10 law, so any gasoline producer can sell ethanol free auto gasoline to anyone in Florida. Even after the Florida mandatory E10 law kicks in next year there are exceptions in the law, just as there are in every other mandatory E10 state, all four of them. Ethanol free auto gasoline can be used by the marine, aviation and public safety industries, and by people with antique and classic cars, off road recreational vehicles and portable tools with small engines. The only problem is, the Florida mandatory E10 law does not require gasoline producers to make ethanol free gasoline for the users to whom they granted exceptions, and neither does any other state that has a mandatory E10 law … big loophole for the producers because the unintended consequences of the RFS mandate in EISA 2007 will drive all of their gasoline production E10 by the end of next year or early 2012, unless the EPA prohibits the blending of ethanol in all premium unleaded gasoline.

  2. Pete Burgher says

    Where can we get a “washer” to remove alcahol from our fuel? It is a major problem here in Florida as it eats fuel tanks and is not good for our rotaxes. Please e- mail me anything you have on removing the stuff from our gasolene. Incidently, our fuel in the panhandle comes from Pascagoula Chevron refinery where the chief chemist says they have no authority to sell us non-alcahol blend. I have started a letter writing campaign to our senator and congressman as it will take a national effort to get congress to remove alcahol from gasolene.Join me in writing yours. Send “washer” info to peteburgher@gmail.com….Thanks, Pete

  3. says

    Kris – Marathon has been making an ethanol free “recreational” auto fuel available in a number of states. If you have a Marathon representative in Maine, give them a call. They did it primarily to serve the marine industry. It is ethanol free auto fuel that meets ASTM D4814 and can be used in aircraft, boats, off road recreational vehicles and even cars for that matter as long as you don’t live in a mandatory E10 state, which Maine is not. We have seen it primarily as 90 AKI, which will not qualify as the fuel needed for Petersen high compression STCs, nor the Rotax 912ULS, but in some areas they have also said that they will provide 91+ AKI, but that is rarer. We have also been advised that they won’t guarantee that they will have it in the future as the ethanol quotas in EISA 2007 swamp the gasoline producers. If you have any further questions please contact me directly, dean@flyunleaded.com

  4. Kris says

    I have been selling non ethanol fuel in Maine for the last few years at a General Aviation airport and I am at the end of my last shipment of what was left of the 87 (93 was run out in August). I have heard rumor of it becoming available again in the spring as I had to have a company from Vermont drive up into Canada to get it for me. He can no longer get it, but thinks they will start refining the non E-10 in the very near future and hopes to hear something by spring.
    We have gone round and round with the State legistlators who most agree that its not a good thing, but they get the kick back for having E-10 statewide. What about the “recreation fuel”? Marathon has been selling a recreation fuel that is non ethanol and is somewhere between 91-92 Octane. I don’t hear anything from Petterson or the EAA about this fuel being approved for aircraft use yet. Any info would be appreciated?

  5. Jonathan says

    The problem with ethanol is it’s a political payoff; payola to the large corporate farmers so they could add another profit center to their balance sheets. It has nothing to do with “saving the planet,” and actually is worse for the environment than drilling for and refining crude oil. After all, the “save the planet” crowd are the same people that jammed 1.6 gallon toilets and compact fluorescent bulbs down our collective throats, without anyone but a tiny few asking for it (I’m okay with the toilets now that they finally flush on one try; the CFLs have mercury (OMG!) that then get thrown into our landfills). On top of the payola angle, it takes a HUGE amount of water to produce–how do the environmentalists answer that?

    So now, you’re reporting that the FREE market has developed a way to remove the ethanol! Amazing.

  6. says

    Surely the world is getting wise to the fact that Ethanol in fuel is a retrograde step for the planet. We live and fly in a developing nation, one where food is for the hungry – not for making ethanol for the rich to burn on the streets. Aeroplanes are fussy creatures, and deserve decent, ethanol, people friendly, pilot friendly fuels.

    I am all up for getting rid of lead, but also for keeping food as food, oil as oil and aeroplanes happy in the sky!

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