More efficient way of converting ethanol to a better alternative fuel

December 3, 2015 by Peter Iglinski

Ethanol, which is produced from corn, is commonly-used as an additive in engine fuel as a way to reduce harmful emissions and scale back U.S. reliance on foreign oil. But since ethanol is an oxygenated fuel, its use results in a lower energy output, as well as increased damage to engines via corrosion.

But now a research team, led by William Jones at the University of Rochester, has developed a series of reactions that results in the selective conversion of ethanol to , without producing unwanted byproducts.

"Butanol is much better than ethanol as an alternative to gasoline," said Jones, the C.F. Houghton Professor of Chemistry. "It yields more energy, is less volatile, and doesn't cause damage to engines."

In fact, Jones was able to increase the amount of ethanol converted to butanol by almost 25 percent over currently used methods. Jones describes his process in a paper just published in the Journal of the American Chemical Society.

Converting ethanol to butanol involves creating a larger chemical molecule with more carbon and hydrogen atoms. Although both molecules have a single oxygen atom, the higher carbon-to-oxygen ratio in butanol gives it a higher energy content, while the larger size make it less volatile.

One method of converting the ethanol to butanol is the three-step Guerbet , which involves temporarily giving up in an intermediate step, then adding them back in to create the final product. One problem with the Guerbet reaction is that an intermediate product—acetaldehyde—can react with both itself and the butanol product to create unwanted molecules.

Jones modified the Guerbet reaction by using iridium as the initial catalyst and nickel or copper hydroxide, instead of potassium hydroxide (KOH), in the second step. While the best current conditions for the Guerbet reaction convert to butanol with about 80% selectivity, Jones' reaction produced butanol in more than 99 percent selectivity. No undesirable side products are produced.

"There's still more work to do," said Jones. "We'd like to have a catalyst that's less expensive than iridium. Also, we want to make the conversion process last longer, which means figuring out what currently makes it stop."

Jones says the process currently terminates after one day because one or more of the substances—the iridium, nickel, and copper—has broken down.

"Once we solve the remaining problems," said Jones, "we may be able to start looking for ways to apply the conversion process in the making of renewable fuels."

Explore further: Cost-saving measure to upgrade ethanol to butanol—a better alternative to gasoline

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not rated yet Dec 03, 2015
I hope they can get this figured out soon. I would really like to see fuel with no alcohol. I'm tired of replacing carbs in small gas engines due to the alcohol dissolving the internal rubber parts.
5 / 5 (3) Dec 03, 2015
The problem is that the entire process of planting and growing corn, converting it to ethanol, and shipping it is actually energy negative. The Ethanol program is yet another farm subsidy that the US doesn't need. Converting it to butanol will take still more energy and infrastructure.

Where does this political stupidity end?
1 / 5 (1) Dec 04, 2015
Ethanol is brutal on antique cars. Not only does ethanol dissolve rubber seals and gaskets, but it absorbs water which causes rust and stalling. Antiques only go through a few tanks of gas per year, so the water buildup is serious. Antique owners would gladly pay much higher prices for butanol-added gas if it's better than ethanol.
Lex Talonis
2.3 / 5 (3) Dec 04, 2015
Well Shakescene21...

The RETARDS could use up ALL the fuel / drain the tank / add a water separator to the fuel lines...

Do some maintenance - Blaming the fuel and it's KNOWN properties in all circumstances, doesn't excuse YOU and them from being a lazy excuse making idiot.
5 / 5 (2) Dec 04, 2015
So let me get this straight Lex, people are supposed to do all this work to support a fuel that rapes our farm land and creates more CO2 emissions than it saves just so some other ill informed people can get a warm fuzzy feeling that they are saving the earth.
not rated yet Dec 06, 2015
... people are supposed to do all this work to support a fuel ...

Well, they could continue ruining their valuable antiques just complaining about it.

That said, if you actually add enough water to ethanol-containing fuel, it will eventually go out of solution and separate by gravity. Then you can catch the gasoline off the top. Problem is, ethanol is used as an octane booster to get crap gasoline to work so what's left over doesn't really work.
not rated yet Dec 07, 2015
Ethanol can also be produced via electro-reduction of CO in the presence of a hydrogen source. This and other methods make proton plasma viable as the transmissible form of hydrogen to support renewable fuel by recombination of captured emissions and hydrogen from gasified wastes and conventional sources such as ice hydrates.
not rated yet Dec 07, 2015

My comment was to present one more reason why ethanol-from-corn gasoline is a costly mistake.

Your "advice" shows that you have no real-world understanding of antique cars. Most antique owners spend at least one hour of maintenance and repair for every hour of driving. Regarding water separators and draining the tank: my 1953 Morgan has a removable glass bowl by the fuel pump which is checked before driving. The gas tank has a drain plug which is used once a year to drain water and sludge. (Prior to ethanol gas, it was sufficient to drain every 5 years.) Your recommendation to use up ALL the fuel might make sense if the car is used once a year, but if it's used several times a month this would be wasteful of gas and destructive to the fuel system and engine.
not rated yet Dec 07, 2015
Since tetraethyl-lead was removed from auto gas, ethanol has served (in part) as a way to get higher octane out of otherwise low quality gas. Some internal combustion engines cannot tolerate ethanol. Example: Racing car, Small boat and Airplane engines. Planes are forbidden to use ethanol (FAA) because ethanol absorbs water, which can freeze after a plane takes off into colder air at 5,000 to 10,000 feet. To get the octane, these planes still use lead. This gas (100 octane low lead costs $6.50/gal) Butinol would be a great solution for small planes if it aids octane. Does it? I have not heard that. The ethanol free gas used by boaters and racers is also very expensive.

The argument that more CO2 is made producing ethanol than it is worth sems OK, but not substantiated. Would like to see somthring on this.
not rated yet Dec 08, 2015
Hemp as the feedstock for butanol and ethanol and tetrahydrofuran and other biofuels

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