Biobutanol - Cobalt Biofuels Raises $25 Million to Accelerate Commercialization of Biobutanol Process

Biobutanol (C₄H₁₀O) or butyl alcohol is a second generation biofuel that can be produced from biomass and can be used either as an industrial chemical or as a transportation fuel. Biobutanol can run in any gasoline engine with no modifications and, like ethanol, has a higher octane rating than normal gasoline. It has the additional advantages that it has a higher energy density than ethanol, can be transferred in our existing pipelines, and can be used as an additive in either gasoline or diesel fuel.

Like ethanol, biobutanol is fermented by microorganisms from sugars, which are broken down from raw feedstocks and mixed with water. For the butanol process, the microbes have been genetically modified to produce an alcohol with a longer chain of hydrocarbons. The fermentation step is followed by a separation step in which the alcohols are separated from the fermentation steep. Since butanol doesn’t mix with water at high concentrations, the finished fuel can be stored easily and transported within existing gasoline pipelines.

Since the cost of the feedstock is the major cost factor, the ability to use low cost non-food feedstocks is a major challenge to cost effective butanol production and much work is being done to develop microbes that can be used with a variety of feedstocks.

The other key research challenge that must be resolved is that butanol production inhibits microbial growth even at low concentrations. The result is that the maximum butanol concentration in the steep of a conventional (ABE)  process is about 1.3 % butanol. The overwhelming majority of the fermentation broth is water and an energy-intensive distillation step has traditionally been used for separation of the butanol from the water. This has caused the production of industrial butanol by fermentation to be abandoned. Much research is now being done to develop microbes are sustainable in higher concentrations of butanol, so as to reduce the power consumption of the separation process.  At the same time, separation process are being developed that are less energy intensive.

Cobalt Biofuels, Mountain View, California, recently announced that it has raised $25 million in equity to accelerate the commercialization of biobutanol.  The Series C equity round was co-led by LSP and Pinnacle Ventures and included both new and existing investors.

"With this round of funding Cobalt Biofuels will move aggressively toward commercial production of cost effective, non-food based biobutanol,” said Pamela Contag, President and CEO of Cobalt Biofuels. New Energy and Fuel reported that Cobalt is using these funds to expand from laboratory scale production to a pilot scale facility with a capacity of 35,000 gallons of fuel per year .

Cobalt has proprietary technologies in microbial physiology, strain development, fermentation and low-energy fuel separation, which they claim make possible a new generation of fuels that burn cleaner, are more cost-effective, and enhance environmental sustainability.   

According to Cobalt, biobutanol is a next generation biofuel that can be used as a standalone transportation fuel, as an additive to gasoline or diesel fuel and as an additive to improve the properties of ethanol.  Unlike ethanol, biobutanol can be used at full strength in today’s automobile engines and can be distributed through existing pipelines.

Cobalt technology will change the biofuel industry by:

• Allowing production of biofuels from local feedstocks based on regional agricultural priorities, including plants that are not subject to food price fluctuations
• Increasing the rate of biofuel production through continuous fermentation
• Improving yield by optimally pairing fermentation organisms with a diversity of feedstocks
• Its patented vapor compression distillation separation system significantly reduces energy and water requirements

Cobalt claims that their process can produce biobutanol from a broad range of non-food feedstocks, as well as more traditional feedstocks including corn and sorghum, thus reducing the risks associated with reliance on a single crop.  As a result, they should be able to site their facilities in a wide range of geographies and use the feedstock available locally.

The cost of feedstock dominates the overall cost of producing biofuel, and the efficiency of biomass conversion (yield) is greatly dependent on the microorganism utilized in the biofuel production process. Cobalt is developing and patenting a high-throughput process to identify the optimal microbe for any selected plant substrate. This technology will allow them to efficiently match organisms to each regionally appropriate feedstock.

They are developing and patenting key production monitoring technologies that will enable the fermen-tation process to run continuously. Their fermentation process differs significantly from the traditional batch processes used today to convert starch to alcohol fuel. Their patented reaction management technology maintains their continuous fermentation process at peak production rates and an optimal concentration of butanol in the steep, for extended periods of time.

The concentration of befoul, in the fermentation steep determines the cost of the energy intensive separation process. Cobalt’s patented fluid separations technology (termed vapor compression distillation, or VCD) removes alcohol from the fermentation steep using one-half the energy required for typical separation techniques.

The concentration also determines the overall water usage of the biorefinery. Cobalt’s technology has the additional advantage of drastically reducing water usage. By capturing, filtering, and recycling the VCD-water back into the fermentation process, it minimizes requirements for fresh water resources and eliminates disposal of large quantities of waste water, 

While details of the process have not been revealed, Cobalt seems to be addressing the technical limitations of traditional fermentation process for production of ethanol. Their ability to develop microbes that can be used with a variety of feedstocks enables wide geographic use of their process as well as enabling the use of low cost feedstocks. Continuous fermentation may enable higher butanol concentrations in the fermentation process and their engineered microbes may be able to withstand a higher concentration in the steep.  Their use of vapor compression distillation (VCD), which I am very familiar with, having developed and implemented such a process, is a major energy reduction element which can also eliminate the use of a fuel for heating, the necessary heat coming from the energy input in the compression step. Their closed loop approach to water usage is a major environmental improvement.

All in all they seem to be addressing the important limitations of conventional processes. Their ability to raise capital in the present "credit crunch" environment is a testimony to their ability to pass the due diligence of the investors. Only time will tell whether their "improvements" are sufficient to enable a reliable, cost effective process.

Comments

[Tom G.]

When I first read about biobutanol several years ago I thought it had lots of promise. It sounded like the transition fuel we need until we can become an electric driven society. It also sounds like a better solution than ethanol.

[Robert G. Schreib Jr.]

WOW! This Cobalt Biofuels may be making a BIG dent in our oil requirements! this is terrfic news! Anyway, a recap here of an idea I already send to DOE and all over the Internet, if we got a virtually endless supply of raw sewage from our cities, couldn't we plow the sewage under areas banned by the EPA for being toxic waste dumps, and use those no food crops ever fields for growing BioFuel plants exclusively, and FOREVER, so that we could eliminate our sewage problem, do something profitable with toxic waste areas, and leave the corn alone for feeding a starving world?

[Natalija]

I'm so glad to see that there are people who think that oil isn't the only source of energy for automotive and other industries.
Divertas delectat, says a latin proverb.
More diverse sources of energy we got more independent we are; and less susceptible to blackmail we get also.

[nathn]

As a microbiologist I would say generating butanol, instead of ethanol, using fermentaion of sugars, is the ultimate natural way of making high energy hydrocarbons; this is how nature made petroleum in the first place. I am very excited and hope that the "big boys" will not get involved and find ways of undercutting the company.

[Martin]

good news, it is very worrying the effect on food production and availability that ethanol presents. I have second thoughts about using an ethanol blend these days. A better option should be at hand.

[bigTom]

While better by far than ethanol (assuming the production issues can be met), butanol production still has many of the problems asociated with ethanol. The chief longterm issue, is what is the effect on soil fertility, i.e. is it sustainable for the long haul? And there is always the issue of competition for natural (or nearly natural) land, versus biofuels, versus food production. Land that is near the boundaries of one use or the other could get converted to the less natural use, by the pressure for biofuels.

Also, we have to be honest about the volume of fuel we can produce this way. The worst outcome would be the message "oil problem solved", when if fact we only have a replacement for a small fraction of our current usage.

[Mark CR UK]

@nathn

Regular readers of The Energy Blog will know that Dupont and BP already have an ongoing relationship generating this technology.

Ultimately the only limitation of this technology like Ethanol is the feedstock issue. Carbohydrates to Fuel is limited by the feedstock.

Lignin-Cellulosic Biobutanol / Ethanol / Methanol will do far more than existing (and controversial) Corn Ethanol.

But again these should be based on fast growing (non damaging) fuel crops or municipal wastes rather than edible crops.

[Rick L.]

Big Tom knows what he is talking about. Butanol is still dangerous for the reasons that Big Tom talked about. Great points and great article. Thanks a bunch, Rick L.

[Mark CR UK]

"Butanol is still dangerous"

Thats an emotive and misleading statement if ever I heard one.

And its not like I didn't acknowledge the issues in the previous statement.

[Organic Grog]

Every had great responses.

[Cyril R.]

BigTom: those are valid concerns.

Although, I imagine that bringing not too large a percentage of the biomass back into the soil in the form of agrichar will help a lot with soil fertility. Combined with carefully returning as much nutrients as possible into the soil, for example by converting the residues into organic fertilizer, and returning that where the biomass was harvested, should alleviate most issues. Occasional crop switching and other techniques can help also. Reducing the amount of water used also appears possible with different plant species.

Perhaps we should stimultate combined heat and power to supply the input heat energy for producing the alcohols. Nuclear and geothermal look very suitable for this purpose.

The food vs fuel is a relevant concern, but it depends on what scale we're talking about. As long as the backbone of our energy and transportation economy is electric, perhaps the impacts from bio-energy as supplemental energy sources could be found acceptable. For example, there are large amounts of corn stover and other agriwaste that are not used very effectively right now. Quite a bit of biomass can also be harvested from forestry and such, as long as the amounts removed per hectare aren't too big (need more thorough scientific study on the limits and impacts of this though). If the harvesting is done not too invasively, and if some of the biomass is returned as agrichar, and the nutrients also, I see no reason why it couldn't score well on the sustainability criteria.

[Cyril R.]

Robert G: it is probably more cost effective and practical to use the sewage as feed for digesters with biogas harvesting, and seperate the nutrients for production of organic fertilizer. The total amount of net energy gain from sewage isn't very large compared to our current oil use anyway.

What Americans need but often don't want to hear is that they have to stop guzzling gasoline.

[Cyril R.]

And guzzling biobutanol isn't going to solve the problem, before you get any funny ideas.

[ktangers]

It would really be good if we could become energy self-sufficient in the near future. We have depended on foreign oil for too long now. This is really exciting research!

[Jim Vitolo]

I don't know about biobutanol. It might not be safe enough for the long term future.

[vania]

i m from brasil i lives sao paulo i think energy in teh world is finish i think companhy do you have half alternative to this im shareholder companhy petroliun but today i m jail mr chairman globo tv mr roberto irineu marinho my prison rue doctor chucri zaidan 46 morumbi at sao paulo sp

[Frank Negolfka]

I agree with Jim Vitolo. Biobutanol can be very harmful towards soil fertility. Over the long haul it could a bad affect on soil. I just don't think this is the right answer.

[danl]

Biobutanol kills the cells that produce it at 1.3%. Isn't it closer to 15% for ethanol? It seems like some good old engineering is helping with the energy and water savings, but they better have some biologists on this as well. Is this anything like what Steven Chu did at LBNL?

[Construction]

This is quite a comprehensive and insightful guideline on Biobutanol and its probable usage. I guess more and more of us should come forward to promote the development of bio-fuels.

[Alternative Energy]

There doesn't appear to be any single biofuel that can replace gasoline... Perhaps we need to consider multiple sources of fuel and multiple types of vehicles. Some for short range others for long range, etc. Some that are hybrid... some all battery... some solar and battery... etc.

[Sony VGP-BPS8 battery]

I guess more and more of us should come forward to promote the development of bio-fuels.

[dell Inspiron E1705 battery]

It seems like some good old engineering is helping with the energy and water savings

[Ronald Brak]

Fermation derived biofuels have great potential for protecting the environment because the fermentation process gives off almost pure CO2 which can sequestered making the process carbon negative. In the future you might be able to buy carbon neutral fuel for your car that is half conventional gasoline and half biobutanol.