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Boosting Biomass-to...Butanol?

From Ohio to California and back on butanol.

An Ohio inventor has taken to the road to promote butanol as an alternative fuel to ethanol as well as his process for producing it from the anaerobic fermentation of biomass waste. The two-stage, dual-path process, which relies on two different Clostridia strains (earlier post), also yields hydrogen as a product.

According to the inventor, David Ramey, his butanol process delivers about 42% more energy than ethanol for a given amount of feedstock, based on the higher energy content of butanol (some 25% greater than ethanol), plus the hydrogen.

Select Properties
a David Ramey, Environmental Engineering, Inc.
b EIA Annual Energy Review, Appendix A1
Formula C4H10O C2H6O Many
BTU/gallon 105K a 84K b 123K b
Vapor Pressure @ 100 F 0.33 psi 2.0 psi 4.5 psi
Air-to-fuel ratio 11.1 9 12–15

Butanol (C4H10O) is a four-carbon alcohol in widespread use as an industrial solvent, with a US market size of some 370 million gallons per year at a price of about $3.75 per gallon (approximately $1.4 billion).

Originally produced by fermentation starting nearly 90 years ago (using Clostridia acetobutylicum), butanol shifted to becoming a petrochemically-derived product in the 1950s as the price of petrochemicals dropped below that of starch and sugar substrates such as corn and molasses. Virtually all of the butanol is use today is produced petrochemically.

In conventional fermentations, the butanol yield from glucose is low—between 15%–25%—and the butanol concentration in the fermentation is usually lower than 1.3%. (Butanol at a concentration of 1% can significantly inhibit cell growth and the fermentation process.) There have been numerous efforts over the years to improve butanol yield by using a variety of techniques to minimize product inhibition.

Environmental Energy Inc.’s Biomass-to-Butanol Process

Ramey took the approach of using two types of microbes in two separate process steps. Other processes had tried multiple strains of bacteria, but in synergy within the same slurry.

The first, Clostridium tyrobutyricum, optimizes the production of hydrogen and butyric acid, while the other, Clostridium acetobutylicum, converts the butyric acid to butanol. (Diagram at right, Click to enlarge.)

Ramey claims his butanol yield from this process is 42% from glucose.

The conventional fermentation process produced a number of products as well as butanol: acetic, lactic and propionic acids, acetone, isopropanol and ethanol production. Ramey’s fermentation only produces hydrogen, butyric acid, butanol and carbon dioxide, and doubles the yield of butanol from a bushel of corn from 1.3 to 2.5 gallons per bushel—equivalent to corn ethanol’s fermentative yield, but with higher heat content and hydrogen as a co-product.

Butanol’s energy content is closer to gasoline than ethanol’s. It is non-corrosive, can be distributed through existing pipelines, and can be—but does not have to be—blended with fossil fuels. Butanol itself could be reformed for hydrogen for use in fuel cells, and the production process itself produces hydrogen.

As good as that might sound, however, there are a number of unknows.

Primarily, the economics of production using Ramey’s process are unproven. He is seeking some $3 million to build a 250-gallon/week prototype and then a 1,250-gallon/week pilot plant. (From 1991, his company, Environmental Energy, Inc., has operated on $1.5 million provided by 40 private investors and by several federal research grants.)

He has produced butanol from his process in small amounts here and there—but for the promotional drive, he and his team bought four barrels of conventional butanol from Ashland Chemical.

Assuming he finds his funding, and the process scales, his plans call initially to sell the butanol into the commercial solvents market to generate a sustainable revenue stream. (It’s a big, existing market, always on the lookout for a less expensive product.)

Ramey ultimately envisions small, turnkey biorefineries of 5 to 30 million gallons per year capacity for small municipalities and surrounding farming communities that would produce butanol as a gasoline substitute.


(A hat-tip to Robert Schwartz!)



I read this article with interest until the line about using petro derived butanol in the car. You'd think after more than 10 years of work that wouldn't be necessary. It doesn't give a good vibe, a bit like finding the hidden battery in a perpetual motion machine.

Lance Funston

Clearly the point was to test its feasability and performance as a fuel in a conventional vehicle on an existing stock of butanol before ramping up to produce it in quantity from biomass.

I think Butanol may very well be the Cindarella Fuel if he figures out how to scale prodution.

John McConnell

It seems to me this is a good example that maybe the best possible transportation fuel isn't even figured out yet. I really get frustrated by hearing the administration say we really can't do anything about global warming -- what, are we a bunch of idiots?? How about saying that we are absolutely going to do something and lets go for it. Certainly there are more ideas like this out there that would be helped by a forward looking federal government instead of with hits head buried in the sand and it's hands buried in the deep money pockets of the oil industry.


The way this is being pitched (sugars from maize rather than e.g. hydrolized wood waste), this is one more attempt at subsidy of farmers rather than energy independence.  Is there any calculation of how much corn would be required to meet demand, vs. how much is available?  Not that I can see.

This is a system with small-to-middling potential, and deserves a similar level of research support.  The big support should be aimed at schemes with much larger potential, from 20% to 100% or more of vehicular energy requirements.


What are the emission characteristics of butanol compared to ethanol and gasoline? We know ethanol is cleaner overall but is butanol?


Hi I posted the trip blog on

But greencarcongress seems to be where the dialog is.

At dramey756 are the proformace data at various Emissions testing facilities across the nation.

Lance is right we did it for demonstration purposes. To make the statement that Butanol replaces gasoline in YOUR CAR today without modifications if we had it.

No one knew the efficacy of Butanol to replace gasoline in all the years.

Now Butanol is at least on the table as an alternative fuel.

Tom we did have Butanol tested in Denver against 100% Ethanol so he said and we are cleaner they looked for 2.5000 and Butanol was 0.1214 grams per mile Hydrocarbons. But I think the HC of 2.5 is more like a gasoline standard than ethanol. Maybe he pushed the wrong toggle. I will post the data in a more formated form (Excel) on the blog in the next couple of days.

All in all it is great being home and back to my critters.

Butanol performed flawlessly everywhere we went. I use to know it was a good fuel but now I am in awe. There is no hidden battery Butanol stands on its own. And ehtnaol at one time was a stepping stone till we found a better solution.



how I can preparation clostridium for produce acetone and butanol?


Frankly I am not even sure if the Oil Companies have a back up plan come the day when Oil supplies are dwindling to nothing but for now as long as people are fed the belief that Oil is our only fuel source available then no one will ever know that we DO infact have a replacement for gasoline I.E. butanol! However with the oil companies having such power will the day ever come when we can start pushing butanol and replacing gasoline? If anything our country won't get anything out of the deal infact I think we are just waiting for Europe to create the alcohol fuel market because no one can see the economical benefits if we are the ones to reach it first... :/



I've recently come across this area after a routine check of wikipedia on biofuels. In case anyone is interested, I've posted about what I found here: (and also off topic in a kater thread on that site). For what it's worth, there are a number of obvious approaches to try that might reduce the problem of butanol build up inhibiting the processes. The most obvious is low pressure fermentation, which would have worked by allowing butanol to boil off as a vapour - only the water would boil off first. Luckily there are a number of variants that could still work; may


Great Idea! Watch out for the Big Oil Thugs that will try to ruin your day... Good luck ,This planet needs a sensible energy solution like yours.


How can one make biobutanol at home ? (in a similar way to homemade biodiesel)?.


How can one make biobutanol at home ? (in a similar way to homemade biodiesel)?.


This could really help third world countries that are heavily dependant on diesel. If the technology were made available biobutanol would explode in a year.

Its a shame that no one really wants to work with a company from a third world to really make this commercial before thye big oil or chemical companies

Eva Markiewicz

I'm shocked I hadn't heard of this before last week. Did this make national news? Why hasn't someone made a documentary about this?


This is all every exciting but it doesn't sound like it will actually be available any time soon.

But I have a few questions anyway...

How to convert a vehicle to run biobutanol?

How much would the conversion cost?

How would an average person get access to the fuel and what would the fuel cost?

henry gibson

In regards to producing Butanol from fermentable bio materials. There is a dual stage process proposed from EEI that increases the efficiency to work from corn or cheese production residues. Other biofermentations can actually produce more complex organic materials from Carbon monoxide , carbon dioxide and hydrogen. These simple molecules can be derived from coal or natural gas at relatively low cost.

Cellulose materials can be converted to these gases as well by very high temperatures and oxygen, but cellulose can also be converted to fermentable sugars by enzymes or simple strong acids. Recovering and reusing the enzymes and acids have been economic issues.

Wet air oxidation, used a hundred years ago to produce vanilla flavoring from wood, can be controlled to produce acetic and other simple organic acids from wood and other cellulose materials including peat. Super critical water oxidation is known to produce large percentages of hydrogen and carbon dioxide from organic materials. Many fermentations use acetic acid and hydrogen to produce other molecules including ethanol. Acetic acid might be used in the production of butanol by being a substrate along with hydrogen for a fermentation process.

Floating an organic, non-water-soluble solvent or oil on top of a bio-reactor solution would probably remove quickly much of the butanol that was produced from the fermentation water solution. Mixing and then allowing the solvent to separate would do it much faster. The solvent would be centrifuged to remove any trace of water, like a cream separator, and then butanol could be evaporated directly from the solvent at low temperatures with vacuum distillation.

Solar energy could be used at the low temperatures required for vacuum distillation. Carbon Dioxide produced by the fermentation is removed at fermentation, solvent mixing and solvent centrifuging stages and will not interfere with the vacuum distillation. Vacuum insulated solar collectors can be used to produce high temperatures even in the winter for distillation. Multiple effect distillation has reduced the energy needed to extract water from sugar solutions, by a factor of four to eight times, for more than a hundred years, and it is also likly that it will also work in butanol production.

One very significant advantage of butanol is that there are far fewer government taxes and laws controlling its production and distribution. Thus it is likely that a small plant that produced a few tens of gallons a day from cornmeal could be owned and operated by a farmer, and the unit would be factory produced at mass production prices like tractors. It would be automatically computer controlled for much of its operation as are modern cars. The other oganics produced by fermentation might not interfere much with butanols use as a fuel in some uses, but may have to be separated and sold or used on site for fuel purposes.

A German maker of Steam Engines has a division that sells long running, packaged internal combustion engine-generator-waterheaters for getting both electricity and heat from fuels. Honda is selling a similar small system for homes that run on natural gas, but both could be used with any fuel including biogas from the waste products of fermentation and any volatile liquid fuels that cannot be sold with the butanol. The heat may be used by the farm and the butanol producer as can the electricity.


The use of food crops is the wrong way to go in the search for alternative fuel sources. The following site proves that we can use something as common as switchgrass for a sustainable biofuels program:

With the kinds of yields that can be harvested with North American native switchgrass there should not be any problem with completely ending our dependence on foreign high risk and expensive petro-oil. The use of switchgrass has so many advantages that it is stunning. Imagine our country powered by low cost butanol made from homegrown crops of grass?


can the corn,wheat,barley used in ferminting be used as animal feed afterwards, or is it toxic to livestock


The issue I'm concerned about is the low butanol concentrations and the potential of being very difficult to separate from the water. There was no talk of a plan for separating the water from the butanol. The only talk is about how good it burns in cars.

Is there any plans to separate the butanol from the water?

I'm all for butanol and other biofuels, and I'm even working at a biodiesel plant this summer. I just think that it will take a little more time and research before butanol becomes an economically viable option.

Rodrigo de la Prida C.

Somebody know how is possible to obtein butanol/ethanol from Stachyose fermentation?

Jim Miller

. Another choice might be BuckyBalls – Carbon 60.

Buckyballs are nanometers in size and are in the shape of a geodesic dome; hence, they might easily receive and give up molecules of butanol. By adding iron to the Carbon 60 at the time the buckyballs are made, a magnet could extract the buckyballs from the biomass and thus remove the butanol. The ability of the butanol to bond and unbond with the Carbon 60 is the science issue. By heating the buckyballs above 100 degrees F, the butanol is released (not sure). Then the buckyballs are returned to the biomass by reversing the polarity of the magnets.

Linda Taylor

I'm interested in looking at homeowner production of butanol from yard/garden/kitchen waste. This could then be used to power the mower/trimmer/snowblower. Any extra could be used in a back-up generator to provide electricity for the home. I would appreciate any suggestions on sites for more information or people working on this aspect of the process.

Ed Gannon

Butanol from Biomass is the answer.

First the biomass:
Many different cellulosic sources (don't use the grain).
Fast growing trees. e.g. polular trees
Drip irrigate to the root ~ 2.5 feet below the surface so that you don't water the grass.

Mechanical chopping and grinding. Mechanically reduce the size as small as possible. A drum/roller mill with holes in roller will yeild super grinding efficiencies.

Enzyme cocktails: technology here is racing.

Convert it to butanol - bringing up the efficiencies here as we speak.

The butanol beauty is the ready market.
We can sell it ASAP and pay for further R&D and production efficienies.

Lets roll !!

Robert Dinse

Actually there is a much cooler way to make butanol than by converting plant feedstocks. There is a company that has invented a reactor, a reverse fuel cell of sorts, that can take CO2, water, and electricity and produce butanol.

Nuclear and coal account for approximately 68% of this nations electricity generation, and neither can be readily throttled down as load falls during the night.

There is enough surplus electrical generating capacity at night to provide the energy needs for our daily commute.

This new technology could simultaneously provide a useful sink for CO2, just as biofuel would, while at the same time not requiring any of the land or displacing food crops. Instead, this could take CO2 that right now is being dumped in the air by coal plants, turn it into an automotive fuel using surplus capacity at night.

This would allow us to continue adding wind generating capacity to the power grid and the peak production times where the wind blows but the demand is low, could be funneled into producing butanol.

If at some point the demand for butanol exceeded the co2 generating capacity of existing power plants, we could scrub co2 from the air.

This could be a big win for the entire planet but you know the oil companies and the big international bankers who finance them are going to fight it tooth and nail.

tim rorer

How does one obtain C. acetobutylicum and C. tyrobutyricum? Also if I have a still for "brewing" ethanol, how do I incorporate the clostridium into the process. I use molasses as my feedstock. Thank you for your assistance.

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