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molecular sieve question

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AOPA(Aircraft Owners and Pilots Association)just had another article on how the lead in aviation has to go pretty soon and ethanol won't work to make a high octane fuel. I already know it can work but after traveling around and seeing some of the employees at some oil distributors and their great interest in doing a good job I got to wondering about this. Moisture contamination is the main concern everybody has so can blended ethanol/gasoline be run through a small molecular sieve to remove moisture just before it goes into the fuel tank of an airplane. If the answer is yes, maybe I just came up with a get rich quick invention. ;)

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This could be as simple as what happens with a GATTS jar, is that right??

 

 

 

Don't know what the mesh is but it's pretty effective with water -vs- Avgas...

 

 

You'd still have to sort out what happens to the liquid that lies below the fuel

 

drain level of the tank... or just purge the empty  tank from the sump every so

 

often to get ALL of what's left in the tank.

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Greengenes, Not sure what the GAATS jar is but I know a molecular sieve has zeolite that attracts water into it's 3 angstrom pores. Ethanol won't fit but not sure about gasoline. I have read where 190 proof can be dehydrated in a five gallon bucket filled with ethanol and some zeolite in a little time. When saturated the zeolite can be baked to expell the water and used again and again. At ethanol plants it's more complex but that is basically what happens. Just wondering about if gasoline is in the mix what happens. If the fuel could be dehydrated as it goes in the tank then phase separation shouldn't be a problem.

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Guest colchiro

Sooo, are we all going to be rich, or just you guys? ::)

 

Just trying to make plans for Monday and need to know if I have to go back to work. :-\

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The GATS jar is just a sample jar that allows you to strain the water out of a fuel

sample and pour the fuel back into your tank. I'm not sure what size the mesh is

but it is very effective at excluding water and impurities and saves you from

scattering the fuel sample all over the tarmac ...

 

I've used one for years.  It's a great little device..

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Greengenes wrote

The GATS jar is just a sample jar that allows you to strain the water out of a fuel

OK, My friend with a Mooney just showed me his the other day. I have a mister funnel with a standpipe with a teflon coated mesh screen that repells water into a little sump. I dump the sump into a jar and collect it and eventually dump it into the tank. I tried dewatering biodiesel with that funnel but that didn't work. In fact it wouldn't even hold water with any trace of biodiesel on the mesh---when dry it will.

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Just dogpiled molecular sieves and found this---kinda interesting.

 

Vaperma Siftek? hollow-fiber polymeric membrane enables the dewatering of a 40:60 ethanol to water vapor mixture into a 99+% w/w fuel-grade ethanol product. There is no need to rectify the ethanol/water blend after evaporation. By replacing the rectifier and the molecular sieve used in a conventional ethanol plant, energy savings as high as 40 % are possible with the innovative membrane permeation process developed by Vaperma. This is equivalent to a cost reduction of 6.4 ?/Gal (1,7?/L).

 

Vaperma has teamed up with Canada's largest producer of ethanol, Greenfield Ethanol (GFE- previously Commercial Alcohols Inc.), to prove its Siftek? membrane technology prior to its industrial scale commercialization, projected for 2008.

 

In addition, Vaperma has teamed up with Dedini, the largest ethanol equipment provider in Brazil, to promote its technology.

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The polymer technique looks good. I assume they're talking about using this only while in

the vapor stage.. but it's a good cost reduction figure ... Is it Iogen that they're working with ??

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AOPA(Aircraft Owners and Pilots Association)just had another article on how the lead in aviation has to go pretty soon and ethanol won't work to make a high octane fuel. I already know it can work but after traveling around and seeing some of the employees at some oil distributors and their great interest in doing a good job I got to wondering about this. Moisture contamination is the main concern everybody has so can blended ethanol/gasoline be run through a small molecular sieve to remove moisture just before it goes into the fuel tank of an airplane. If the answer is yes, maybe I just came up with a get rich quick invention. ;)

 

 

I am not sure why you are so concerned about the E10 going into the plane unless the E10 was mishandled in storage. I always thought the concern was water in the fuel bladder in the plane and the addition of e10 might not have enough h20 carrying capacity to avoid phase separation once it is exposed to the water bottom of the plane's bladder. I do not know if any method exists to draw h20 out of a gas/ethanol blend. Separately drying is relatively easy- Zeolite or mole sieves for ethanol and several methods for gas. Cimtek filters of Bement IL came up with two styles of water separation filters for diesel and gas filters back in the '70s and '80s. One is for gravity- the paper filter media in this one is coated and as the fuel flows thru it the water is repelled and runs to the bottom petcock of the spin on filter (note that petcock is normally closed so if a lot of water is present this would have to be opened to allow escape). The other type is a saturate and plug type for pressure type setups- ok for safety but will plug quickly with more than several ounces of water. In this type a cornstarch polymer is embedded in the filter media-this swells in the presence of water and plugs the filter. It is best used as a failsafe. To my knowledge neither of these will work in an ethanol blend. Cimtek may have come out with something new for blends since this but I do not know what the product name is- i will check their website.

 

Thanks for the info on the GATTS jar and the membrane. I have seen various membranes touted but have not heard much about them going into full blown ethanol production facilities much yet. They will if they pan out since heating/regenerating the mol sieves does take a fair amount of energy and excess sieve capacity to allow for this cycle. I would have to double check on this but I am thinking that the the mol sieves are only used in vapor phase- perhaps the membrane is too- if so, even if gasoline could pass through with ethanol- it may not be safe or practical to do so in a mobile fueling situation.

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