THE Butanol Thread (merged)

[BLove]

Michael H. Brown, an ethanol/steam engine/mechanical pioneer wrote in his book "Brown's Second Alcohol Fuel Cookbook" about a bacteria called Clostridium acetobutylicum that could be used on the small scale to ferment starchy feedstock to butanol (liquid alcohol-type fuel that floats on water and can therefore be collected without distillation - yes really), acetone, and ethanol without any other yeast or enzymes. Brown's chapter on the subject is sketchy at best, but the book was published in 1981. Can anyone out there direct me to more information? Or better yet, does anyone have experience making or even using butanol?

[dauterman]

Hi,

I did a quick internet seach and came up with:

http://www.butanol.com/

http://www.ars.usda.gov/research/public ... 115=149057

http://running_on_alcohol.tripod.com/id24.html

http://running_on_alcohol.tripod.com/id1.html


Butanol is an alcohol. Alcohols are a family of chemical compounds that include methanol, ethanol and propanol. Some of the more common uses for alcohol are alcoholic beverages (ethanol), chemical solvents and fuels. Initially, EEI will produce and market butanol as a solvent, with the future intent of selling butanol on the fuels market.

Butanol is presently manufactured from petroleum. Historically (early 1900s – 1950s) it was manufactured from corn and molasses in a fermentation process that also produced acetone and ethanol and was know as an ABE (acetone, butanol, ethanol) fermentation. However, as demand for butanol increased, production by fermentation declined mainly because the price of petroleum dropped below that of sugar when the USA lost its low-cost supply from Cuba around 1954.

The historical ABE fermentation technology produces a variety of fermentation products. The ABE process uses bacteria to produce Acetone Butanol and Ethanol. This fermentation process yielded a 6:3:1 ratio of Butanol, Acetone and Ethanol.

That is, for each bushel of corn you would garner (1.3) gallons of Butanol (.7) gallons of Acetone and (.13) gallons of Ethanol with concentrations of 1-2%.

If you compared ABE yield and concentration to the Yeast fermentation process for producing Ethanol, which yields 2.5 gallons of Ethanol from a bushel of corn, with concentrations of 10-15% it becomes very clear why Ethanol was chosen as an alternative fuel source over Butanol in the 1970's and 80's.

Butanol, a superior liquid fuel, can be produced anaerobically by Clostridium beijerinckii or C. acetobutylicum from agricultural biomass. However, the cultures are strongly inhibited by the butanol. In bioreactors, butanol concentration higher than 25 g/L is rarely reached. Low butanol concentration hampers economic recovery of this fuel. Pervaporation, gas stripping, and liquid-liquid extraction have been reported to be energy efficient techniques for the separation of butanol from fermentation broth.

Butanol is another amazing alternative fuel, because it can be made from things like rice straw and old newspapers. It has as much energy as gasoline (BTU'S/gal), it burns with the same air/fuel ratio, and it will even mix with gasoline which means that you don't have to drain your tank first in order to use it. You don't even have to re-tune or adjust your engine. The best part is that it can even be made from lawn clippings and leaves.

While I have read various pieces of literature on the subject, I only have personal knowledge of two people who ever tried to make it. The first was Pete Charles, the same person who designed the Charles 803 alcohol still...Pete tried to make it from lawn clippings (ordinary grass). It is a biological decomposition, via an anaerobic process (no oxygen), but the smell was so bad, and extremely difficult to get rid of the smell afterwards. In fact it was a serious nuisance! Several other by-products, including butyric acid, are produced (although in small amounts), but they are can be a serious danger to eyes, nose, and skin.

The other person I met during this period, about 20 years ago, was Dr. Sydney Levi, a former chemistry professor, chemistry textbook author, and holder of many patents involving plastics extrusion processes. He was going to build a huge $3 million dollar plant in Fresno, Calif. and convert rice straw to butanol. He said he had the funding in place and he was working on his proposal full time when I met him. He had made it in his laboratory many, many times. I spent over an hour with him, he showed me the plant diagrams and chemical processes for how the process would work...Somehow, the project died.

Butanol is a pretty exotic fuel, not something you want to make in your backyard, as the smell is truly horrible -- not so much the fuel itself, but the cellulose-eating bacteria, like very smelly socks times 1,000!

[Devil]

...butanol (liquid alcohol-type fuel that floats on water and can therefore be collected without distillation - yes really)

Please get your facts straight. Butanol IS an alcohol. All organic chemicals that end in -ol are alcohols and it does not float on water. There are actually three isomers 1-butanol or n(ormal)-butyl alcohol, 2-butanol d or sec-butyl alcohol and 2-butanol l, which has a mirror image structure of the sec- variety. There is actually a fourth butanol, trans-butyl alcohol, which has a non-linear molecule, but this may be ignored as it does not occur naturally. They all have the same chemical formula but very different molecular structures and physical properties

1-butanol, the commonest type, is 100% miscible with water and so DOES require distillation. Unfortunately, this is very difficult for two reasons a) the boiling point is 117.4°C, so you have to boil the water off first, hopefully leaving the alcohol in the still bottoms and b) it forms an azeotrope with water at 57.5% alcohol which boils off first at 92.7°C. This means that if your mash contains less than 57.5% butanol, you will boil it all off as a constant composition mix of 42.5% water/57.5% butanol and you will be left with the excess water in the bottoms. The two 2-butanols suffer from a similar fate with a BP of 99.5°C, azeotropes of 73.2% butanol at a BP 87.0°C, so would be even more difficult to distill.

Let's imagine you have a 90% solution of mixed butanols in water (I don't know how you would obtain it, but I have a vivid imagination!) The first distillate will be the 2-butanol/water azeotrope at 87°C. If there were still some water after all this had boiled off, the second phase would be the 1-butanol/water azeotrope at 92,7°C. When this had all boiled off, you would be left with ± pure 1-butanol. However, this is hygroscopic and will soon start absorbing humidity from the air, so you would have to repeat the process, losing more along the way. Now, tell me which liquid has the highest latent heat of vaporisation? I'll save you the bother of looking it up, it's water, so the distillation will be much more energy-intensive than distilling ethanol with 96% ethanol/4% water as its azeotrope at the lower temp of 78.17°C.

May I respectfully suggest you research facts before quoting misleading data?

[gg3]

Good summary, dauterman, especially for quick research.

I did a more lengthy research project (online research, not hands-on) on butanol a few years ago for a small think-tank. I could see about getting permission to send you the paper or to publish it here. Chances are that, if anything, we'll publish it on another site instead, and then direct you to that site.

Some things I remember from the project, most of which were also covered by dauterman:

Butanol has excellent properties as a fuel, including that it can be readily combined with gasoline, diesel, and biodiesel fuels. Biodiesohol is a promising application.

Clostridia used in butanol production are related to strains that are known to cause disease and/or produce deadly toxic byproducts; there is potential for cross-contamination by common high-risk strains; prevention requires somewhat expensive procedures.

The foul smell cannot be avoided, and it is a good reason for anyone who lives or works nearby to object mightily to a butanol plant.

There are some toxic byproducts that have to be handled carefully and treated as hazardous materials.

We concluded that the downsides outweighed the upsides, and that ethanol was a more viable fuel from a production standpoint.

[BLove]

butanol; n-butanol;
butyl alcohol Budavari et al. 1989

Molecular Formula C4H10O
Chemical Structure CH3CH2CH2CH2OH
Physical State refractive liquid Budavari et al. 1989
Molecular Weight 74.12 Budavari et al. 1989
Melting Point -90øC Budavari et al. 1989
Boiling Point 117-118øC Budavari et al. 1989
Water Solubility 9.1 mL/100 mL @ 25øC Budavari et al. 1989
Density d20/4øC, 0.810 Budavari et al. 1989

This would indicate that n-butanol is NOT 100% miscible with water (@ 25 deg. C, which is approximately the temperature at which the fermentation would take place). I have a limited amount of information to work from (at least on the scale that I'm interested in); I welcome corrections because I'm looking for facts, but in this situation am not sure whose information is true (I haven't personally seen anything that would indicate that butanol is 100% miscible in water).

Also, if butanol doesn't float on water (and I have yet to be convinced of this, though am open to the possibility) it is allegedly possible to remove butanol from water by mixing the solution with vinyl bromide (in which butanol is more soluble than in water), draining it off (the vinyl bromide/butanol solution is denser), and then letting the vinyl bromide evaporate (boiling point 15.6 deg C???), leaving butanol (the vinyl bromide would be condensed and reused). I've also read that ethanol can be separated from water in a similar fashion using castor oil, except castor oil/ethanol will end up floating on the water rather than sinking.

Is there some compound that - a) dissolves butanol readily; b) is insoluble in water; c) boils at a temperature sufficiently different from that of butanol to facillitate efficient separation; and d) is less toxic/more accessible than vinyl bromide - which could be used to concentrate butanol based on the same principle as in the examples above?

I apologize for my ignorance in this matter - I dropped out of high school and have been too busy trying to build a village in the middle of the woods to be as up on my chemistry as I should be. I ask the questions because someone else may have already researched/experimented in this realm, and might also be willing to offer information that would save me some time and/or headache.

As far as the efficiency/feasibility of butanol fermentation goes - at this point I'm planning to use ethanol as my primary fuel, and am interested in small-scale butanol fermentation primarily because of the acetone, which could be used to clean used fuel/air/oil filters, spark plugs, injectors, etc. (whatever parts there are that will need to be salvaged after industrial production ends), dissolve/recycle plastics, and make smokeless gunpowder. The butanol would just be a useful byproduct (though it twice as much of it would be produced, of course), and having the ability to make a wide range of organic compounds from the same feedstock seems like a good idea to me (particularly when I won't be able to purchase them off the shelf anymore).

Thanks for you time and assistance,
BLove

[Devil]

OK: Miscibility of butanol: butanol, when agitated with water in proportions higher than its true solubility will form an unstable emulsion. As this will be partially micellar (esp. n-butanol), any settling will be very slow and incomplete and will sequester more water than its true solubility would imply. Any cloudiness in either phase would indicate emulsification. If it does separate (which will happen only with pure water: any other product with surfactant properties, even in extremely small proportions, may render the emulsion stable and separation will not occur), then the lighter phase will be the azeotrope of 57.5% butanol, and will distill as such.

You may not be aware that funny things happen when you mix alcohols and water. For example, if you mix 1 volume of ethanol or other soluble alcohol with 1 volume of water, you will get much less than 2 volumes of solution (approx 1.8 volumes, depending on the alcohol) and its surface tension and viscosity will be much lower than either those of water or the same alcohol. This is because of the polarity of the alcohol being weaker than that of the water: the OH group tends to lock with a shared H+ ion in the water as a result of hydrolysis. This is the also the reason why C4 and higher alcohols have a lower solubility but a good miscibility.

As for your last paragraph, is it not tinged a great deal with a teeny-weeny bit of paranoia? If you plan to make your own ethanol, have you carefully read the contents of http://www.atf.treas.gov/regulations/27cfr19.html ?

[kuraku]

I came upon the butanol.com web site and searched for more information. This year-old thread is one of the better compilations of information I found, so I'm adding to it.

The butanol.com web site links to a 103-page pdf report <http://www.osti.gov/bridge/product.biblio.jsp?osti_id=843183> prepared by EEI under contract to DOE, containing the information behind the floats-on-water story.

Butanol and water form an azeotope that is 55.5% butanol, 45% water. The azeotrope boils at 93C, lower than either of its components. Quoting the report, p. 57:

EEI’s novel process takes advantage of the fact that the 55% Butanol azeotrope separates into two liquid phases upon setting. The upper layer constitutes 71.5% of the total volume and is 79.9% butanol while the bottom layer represents the remaining 28.5% of the volume but is only 7.7% butanol. Decantation of the top layer therefore permits an increase in concentration of 24.4% in the butanol process stream with no additional energy expended. The process uses 2 distillation columns and a decanter to extract butanol from an aqueous solution. The first column drives the 93 C azeotrope out the top of the column and removes the majority of the water out the bottoms, eliminating the need to vaporize water and drive it out the top of the column. The vapor out the top of column is condensed, fed to a decanter which is used for reflux feed to the first column. The bottom layer from the decanter (7% butanol) is fed back into the feed stream of the first column. The top layer from the decanter, which is high in butanol, is fed to the second column. This process stream off the top of the decanter represents almost 96% of the total butanol fed to the first column (see math below). The second column again drives the 93 C azeotrope out the top of the column, the vapor mass being proportional to the amount of water fed to the column. The high boiling butanol product goes out the bottom, eliminating the need for high temperatures to drive butanol out the top of the column.

[uNkNowN ElEmEnt]

September 12, 2006
Butanol is a four-carbon alcohol. Alcohols also include methanol (1-carbon), ethanol (2-carbon) and propanol (3-carbon). Butanol is used primarily as an industrial solvent. The worldwide market is about 350 million gallons per year with the U.S. market accounting for about 220 million gallons per year. Butanol currently sells for about $3.70 per gallon in bulk (barge). Butanol can also be a replacement for gasoline as a fuel without major engine modifications and can be shipped through existing fuel pipelines.

Butanol has a high energy content (110,000 Btu per gallon for butanol vs. 84,000 Btu per gallon for ethanol). Gasoline contains about 115,000 Btu's per gallon. Butanol is six times less "evaporative" than ethanol and 13.5 times less evaporative than gasoline, making it safer to use as an oxygenate in Arizona, California and other states, thereby eliminating the need for very special blends during the summer and winter months.

Even the U.S. Department of Energy funded a study of butanol, under a federal DOE/STTR grant from the Department of Energy through the Small Business program (DE-F-G02-00ER86106), in association with Dr. S.T. Yang of the Ohio State University.

There has been little to no effort to promote butanol as an alternate fuel because of historically low yields and low concentrations of butanol compared to those of ethanol; that is, for each bushel of corn you would garner (1.3) gallons of butanol (0.7) gallons of acetone and (0.13) gallons of ethanol with concentrations of 1-2%.

Butanol is presently manufactured from petroleum. Historically (early 1900s - 1950s) it was manufactured from corn and molasses in a fermentation process that also produced acetone and ethanol known as an ABE (acetone, butanol, ethanol) fermentation. However, as demand for butanol increased, production by fermentation declined mainly because the price of petroleum dropped below that of sugar when the U.S. lost its low-cost supply from Cuba around 1954.

If you compared ABE yield to that of the yeast ethanol fermentation process, the yeast process yields 2.5 gallons of ethanol from a bushel of corn; with concentrations of 10-15% it becomes very clear why ethanol is considered a better alternative fuel source over butanol. One company, Environmental Energy Inc. (EEI) has developed and patented technology that they believe overcomes the limitations that have to date kept the cost of butanol production from corn and other forms biomass high.


EEI claims they can produce 2.5 gallons of butanol from corn with no acetone or ethanol, whereas most other processes have not been able to achieve better than 1.3 to 1.9 gallons of butanol per bushel and still utilize an ABE process. Some experts in the automotive industry have been publicly praising butanol, so don't count it out by any means, as new flex-fueled vehicles come to market.

-- Scott Sklar

Scott Sklar is President of The Stella Group in Washington, DC, a distributed energy marketing and policy firm. Scott, co-author of "A Consumer Guide to Solar Energy," uses solar technologies for heating and power at his home in Virginia.

[mekrob]

Interesting.

Butanol has a high energy content (110,000 Btu per gallon for butanol vs. 84,000 Btu per gallon for ethanol).

Since it would be used for transportation, you can't look solely at energy content. You must look at the mileage that you get from it. For example, it's often quoted that ethanol has only 70% the amount of energy as gasoline. But this doesn't matter since the drop in efficiency is only about 10%. Would a Butanol powered car do as well as a gas powered one, or better or worse? That's a more important stat.

[Tanada]

A correspondent of mine on a writers group I belong to sent me the following message and I thought sharing it might spur some discussion.

Acetylene is normally stored disolved in acetone. The 1911 Encyclopedia Britanica lists one method of manufacturing acetone but there was an early method of industrial biotech that was introduced in 1916 and was used until the 1960s when petroleum got so cheap that the fermentation method could no longer compete economically.

The Clostridium family includes the bacteria that cause tetanus and botulism but there is also Clostridium acetobutylicum otherwise known as the "Weizman organism" after the man who discovered that this bacteria would eat sugar, starch or even cellulose or lignin and excrete acetone, n-butenol and ethanol (in a ratio of 6:3:1) and that this could be done as an industrial process using the physical plant of a distillery.

This was exciting news for the British Admiralty in 1916 because they needed acetone as part of their process of manufacturing cordite.

What could be even more exciting news for the folks in Grantville is that n-Butanol, which was considered a waste product in 1916, can be used as high octane gasoline.

Sadly, n-butanol is not the isobutanol isomer that can be polymerized to produce the impermeable to gas artificial rubber used in tire inner tubes or the "brutal rubber" suit worn when dealing with poison war gases. Isobutanol is also the stuff that can be copolymerized with styrene to make the synthetic rubber that we use in most tires today, however, this ain't it.

Anybody know how feasible it is to change the n-butanol isomer to the isobutyl isomer?

[Tanada]

More info from Butylfuel.com

Why has there been little to no effort to promote butanol as an alternate fuel?
Prior to the success of ButylFuel, LLC’s work, production of butanol from corn and other biomass has been stymied by the lack of technology to make it economically viable. The problem has been historically low yields and low concentrations of biobutanol compared to those of bioethanol.

The historical ABE fermentation technology produces a variety of fermentation products. The ABE process uses bacteria to produce Acetone Butanol and Ethanol. This fermentation process yielded a 6:3:1 ratio of Butanol, Acetone and Ethanol.

That is, for each bushel of corn you would garner (1.3) gallons of butanol (0.7) gallons of acetone and (0.13) gallons of ethanol with concentrations of 1-2%.

If you compared ABE yield to that of the yeast ethanol fermentation process, the yeast process yields 2.5 gallons of ethanol from a bushel of corn, with concentrations of 10-15% it becomes very clear why ethanol was chosen as an alternative fuel source over butanol in the 1970's and 80's.

ButylFuel, LLC's patent changes everything. We are now able to produce yields of 2.5 gallons of butanol per bushel of corn.


ButylFuel, LLC's patented discovery and the economics did not exist to pursue Butanol versus Ethanol as a viable alternative to gasoline until now.

What does ButylFuel, LLC bring to the table when it comes to producing butanol?

ButylFuel, LLC has developed and patented technology that overcomes the limitations that have to date complicated and kept the cost of butanol production from corn and other forms of biomass high. BFL is now able to produce 2.5 gallons of butanol from corn with no Acetone or Ethanol, whereas others have not been able to achieve better than 1.3 to 1.9 gallons of Butanol per bushel and still utilize an ABE process. Further, BFL’s technology generates hydrogen which is likely to receive additional attention as an alternative fuel in the future. In fact, taking into account the hydrogen production, BFL can produce 42 % more energy from a bushel of corn than is typically produced by a corn-to-ethanol plant – 25 % of the difference lies with the butanol and 18 % comes from the hydrogen.

What are the economics of the ButylFuel, LLC process?

This will not be known in detail until we complete testing on the B-100 (100 gallons butanol per week) Demonstration model and the B-1,000 pilot plant. However, we can share the results of estimates we developed to established the merits of proceeding with these phases of the work.

Our preliminary cost estimates suggest that we can produce biobutanol from corn for about $1.20 per gallon, not including a credit for the hydrogen produced. This compares with ethanol production costs of about $1.28 per gallon. Taking into account the higher Btu content of butanol, this translates to 105,000 Btu per dollar for butanol and 84,000 Btu per dollar for ethanol with corn at $2.50 per bushel. As a further point of reference, butanol produced from petroleum costs about $1.35 per gallon to manufacture.

The economics of the ButylFuel, LLC process will be even more attractive when waste material is used as feedstock instead of corn and the price to produce a gallon is $0.85 . In such cases the need and cost to grow and prepare the corn for fermentation, by far among the major cost items, are eliminated.

[Boris555]

If n-butanol can be made to burn in current IC engines with no modifications, and has the ability to mix with regular gas, then it has a chance.

Cracking out the acetone would be important, though.

Making it with waste silage is even better.

[Tanada]

If n-butanol can be made to burn in current IC engines with no modifications, and has the ability to mix with regular gas, then it has a chance.

Cracking out the acetone would be important, though.

Making it with waste silage is even better.

I could see a modified plant that does both Ethanol and Butynol, one from the corn and the other from the stalks. Use the Acetone made in the process as fuel for the boilers/dryers in whole or in part and you just save yourself a bundle on EROEI and dollar costs.

[steam_cannon]

The 1911 Encyclopedia Britanica lists one method of manufacturing acetone but there was an early method of industrial biotech that was introduced in 1916 and was used until the 1960s when petroleum got so cheap that the fermentation method could no longer compete economically.

Old school, I like it! Nice find Tanada!

[Graeme]

Butanol Breakthrough – Could This Biofuel One Day Replace Gasoline?

Butanol may be used as a fuel in an internal combustion engine. Because its longer hydrocarbon chain causes it to be fairly non-polar, it is more similar to gasoline than it is to ethanol. Butanol has been demonstrated to work in vehicles designed for use with gasoline without modification. University of California, Berkeley, chemists have engineered bacteria to churn out a gasoline-like biofuel (butanol) at about 10 times the rate of competing microbes, a breakthrough that could soon provide an affordable transportation fuel.

The potential feedstocks are the same as for ethanol: energy crops such as sugar beets, sugar cane, corn grain, wheat and cassava, prospective non-food energy crops such as switchgrass and even guayule in North America, as well as agricultural byproducts such as straw and corn stalks.

The advance is reported in this week's issue of the journal Nature Chemical Biology.

Biobutanol can be produced by fermentation of biomass by the A.B.E. process. The process uses the bacteriumClostridium acetobutylicum, also known as the Weizmann organism.

oilprice

[Tanada]

Somewhere in the archives is at least one thread where I brought this concept up and got raspberries from the usual suspects as a result.

[Tanada]

Bumped in light of Graeme's new Butanol thread.

[PrestonSturges]

Butanol production has also been done photosynthetically with cyanobacteria, but I'm not really that sold trying to do photosynthesis in flasks. Better to grow biomass and let the bugs ferment it.