According to estimation from DuPont the biofuel industry worldwide will grow from a $50 billion opportunity today to a $75 billion opportunity by 2015. Besides the already well known biodiesel and bioethanol a further promising biofuel is on the rise. Biobutanol! While being currently used as an industrial solvent and mostly produced via petrochemical processing, butanol derived by renewable resources bears an impressive potential to be used as a biofuel.
As a fuel, it can be easily transported in already existing infrastructure and does not require flex-fuel vehicle pipes and hoses. It can even be used alone in combustion engines. The energy density of biobutanol is about 4% less than gasoline, but that’s hard to notice compared to ethanol’s 27% drop.
Biobutanol can be produced from the same feedstock as bioethanol mainly in the use of bacteria rather than yeast. The drawback has been the price of its production. Low productivity of the fermentation process and the expensive cost of separating the fuel from the water have been restricting.
Now, technologies to improve the fermentation process and to reduce energy consumption in the separation phase have been developed. Genetically modified versions of the bacterial strains of Clostridium to improve butanol tolerance and yield are critical as bacteria are poisoned by the butanol they produce once its concentration rises above 6%.
A couple of companies and joint ventures are currently working to harness these technologies for industrial purposes.
The Californian firm Cobalt Biofuels already runs a pilot plant and will proceed to a commercial plant by 2012. The company has signed a Cooperative Research and Development Agreement (CRADA) with the U.S. Navy to develop a viable process for the conversion of biobutanol into full performance jet and diesel fuels. Earlier in 2010, Cobalt signed an agreement with Fluor Corporation to provide engineering consulting services as the company gears up to commercialize its biobutanol production technology.
An interview with Cobalt Biofuels:
UK-based biotech company Green Biologics developed a unique collection of heat-loving bacteria and thermostable enzymes. Green Biologics is focused on the retrofit of ethanol plants as well as providing fermentation and process technology solutions for existing and new build biobutanol plants in China, India, Brazil and the US. In China, the company cooperates with two biobutanol producers to provide step change improvements in their process economics. The firm’s technology has demonstrated a cost saving of over 30% reducing the production cost of biobutanol by over $400/ton.
Butamax Advanced Biofuels LLC, a joint venture between DuPont and BP is primarily focused on the fuel market. In November 2010 Butamax announced achievement of several milestones in its plan to commercialize biobutanol for the transportation fuel market. Butamax is conducting research across the globe as it prepares for commercial launch. A laboratory to accelerate commercial designs for sugarcane-to-biobutanol in Paulinia, Brazil has been established. In addition to Brazil, research is being conducted in India, the United Kingdom, Germany and the United States. The JV expects to enter the US market on a commercial basis in late 2012.
See a video about Butamax biobutanol from DuPont:
Gevo aims to retrofit ethanol capacity to produce butanol. In 2009 Gevo was awarded up to about $1,780,000 in a combined USDA/DOE grant to develop a yeast fermentation organism that can cost effectively convert cellulosic derived sugars into isobutanol. The company announced in November 2010 that its biobutanol is the first isobutanol to be listed in the EPA’s Fuel Registration Directory and is approved for blending with gasoline. Gevo will soon begin the retrofit of its first 22m gal/year ethanol facility in Minnesota to produce 18m gal/year of isobutanol.
German specialty chemical company Lanxess has invested $10million in Gevo for the development and production of biobased isobutene for the manufacturing of rubber. Gevo anticipates initial commercial production of their isobutanol in 2012.
Short video about water – butanol separation:
Cathay Industrial Biotech
The Chinese biobutanol producer Cathay Industrial Biotech is currently producing corn derived n-butanol for chemical applications at a 100,000 ton/year scale in its biorefinery in Jilin Province, China. The production facility, which uses the acetone-butanol-ethanol fermentation route, started in 2009 and gains 65-70% butanol, 20-25% acetone and 5-10% ethanol. The company now plans to build its second biobutanol facility either in China or in the US. Production capacity is expected to be about 100,000 tons/year.
In addition to the already mentioned, a few further companies like Tetravitae Bioscience, Metabolic Explorer and ButylFuel are into biobutanol business. But unfortunately, they have either not proceeded out of the R&D stage or announced any plans for commercialization of their technologies.
Watch the ButylFuel Story:
Anyway, regarding the unique advantages of biobutanol as biofuel or intermediate for the chemical industry it is obvious that its implementation has the potential to add significant value to the global biofuels and green chemistry market.