Ethanol (=alcohol) added to gasoline

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    Ethanol Gasoline
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In the United States, gasoline commonly contains up to 5% ethanol as an additive, which is used to increase the effective octane number and replace toxic substances like MTBE and tetra-ethyl lead. Purifying ethanol to 99% is challenging due to its tendency to absorb water, with simple distillation achieving around 90% purity. High-purity ethanol can be purchased from lab supply companies, but it loses purity quickly after opening. The U.S. is moving towards a higher ethanol blend, with legislation supporting the addition of bio-ethanol to fuel. Ethanol's use in gasoline is seen as a less toxic alternative to previous additives, though concerns about its properties remain.
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1. Incredibly it appears that in the United States gasoline may have ethanol in it as an additive. Up to 5% can be ethanol in the fuel sold there. Does anyone know if this is accurate?

2. How do I purify ethanol (=alcohol) to 99%?

3. Where do I buy 99.9% pure ethanol?
 
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Gasoline is a mixture of all sorts of hydrocarbons typically around 5-8 C long so a bit of ethanol isn't going to make a lot of difference.

You can purify ethanol by simple distillation although it's hard to get above 90% because ethanol readily absorbs water from the air.

You can buy high purity ethanol from the normal lab supply companies, sigma-aldritch etc but it isn't going to be high purity for long once you open the bottle.
 
There's nothing particularly shocking about oil companies adding ethanol to the fuel you buy. More curiously, incentive/legislation is made such that bio-ethanol is added to pump fuel in many countries, which is understandably controversial.
 
Ulysees said:
Incredibly it appears that in the United States gasoline may have ethanol in it as an additive. Up to 5% can be ethanol in the fuel sold there. Does anyone know if this is accurate?

In modern days, Ethanol is being added to gasoline to raise its effective Octane number. It is basically a replacement for MTBE and tetra-ethyl lead. tetra-ethyl lead was originally used for raising a fuel's resistance to spark knock, followed by MTBE which didn't contain lead, but turns out to be carcinogenic. Basically, Ethanol is one of the only additives that can be used with gasoline that is easy to manufacture and does not have heavily toxic or carcinogenic effects like tetra-ethyl lead or MTBE. Still, I think that many toxic properties of gasoline additives such as MTBE are blown far out of proportion.

http://en.wikipedia.org/wiki/Tetra-ethyl_lead

http://en.wikipedia.org/wiki/MTBE
 
Ulysees said:
1. Incredibly it appears that in the United States gasoline may have ethanol in it as an additive. Up to 5% can be ethanol in the fuel sold there. Does anyone know if this is accurate?

2. How do I purify ethanol (=alcohol) to 99%?

3. Where do I buy 99.9% pure ethanol?

Your local liquor store has pure grain alcohol which is 98% alcohol.

On the other note, with the United States requiring 10% ethanol in gasoline, it is setting up the infrastructure to switch to E85 in the distant future.
 
sirzerp said:
Your local liquor store has pure grain alcohol which is 98% alcohol.
That would be a special liquor store. Alcohol forms an azeotrope at lower concentrations, so stuff above 96% is going to be hard to find. The usual methods for getting higher concentrations are discussed in fuel distillation sites.

http://running_on_alcohol.tripod.com/
 
sirzerp said:
Your local liquor store has pure grain alcohol which is 98% alcohol.

Not in Ohio you won't. Kentucky on the other hand...:devil:
 
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Sorry, wrong thread, ignore this.
 
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