n-Butanol is a commercially important alcohol that is considered by some to be a strong candidate for widespread use as a motor fuel. n-Butanol is currently produced via chemical synthesis almost exclusively. The dominant synthetic process in industry, the acetaldehyde method, relies on propylene derived from petroleum [1]. The U.S. market for butanol is 2.9 billion pounds per year [2]. Currently, the primary use of n-butanol is as a solvent, however, several companies including British Petroleum and DuPont are developing methods to utilize bacteria to produce n-butanol on a large scale for fuel [3]. Microorganisms capable of producing n-butanol by fermentation are Clostridia acetobutylicum, C. beijerinckii, and C. tetanomorphum.

n-Butanol has several characteristics that make it a viable alternative fuel option. It has an energy density that is similar to gasoline. Additionally, it could power a combustion engine with minimal or no modifications. In either a blended or neat form, n-butanol could be easily integrated into our current infrastructure.

The following is a n-butanol pathway map. For the biological pathway, organisms which carry out the pathway are given above, but other organisms may also carry out this biochemistry. Follow the links for more information on compounds or reactions.

[1] Tsuchida T., Sakuma S., Takeguchi T., and Ueda W. (2006) Ind. Eng. Chem. Res. 45, 8634-8642.
[2] Ezeji, T.C., Qureshi, N., and Blaschek, H.P. (2007) Process Biochemistry 42, 34-39.
[3] http://www2.dupont.com/Biofuels/en_US/index.html