Biobutanol production

BP has investments in an ethanol plant with DuPont and Associated British Foods. It is also investing in cellulosic ethanol research and developing jatropha as a biodiesel feedstock. BP and DuPont are planning a biobutanol demonstration plant and BP would like to eventually convert their ethanol plant to biobutanol production. BP has a 400 million investment with Associated British Foods and DuPont to build a bioethanol plant in the U.K. that may be converted to biobutanol. It has spent 500 million over 10 years at the Energy Biosciences Institute in California to research future biofuels and 9.4 million over 10 years to fund the Energy and Resources Institute (TERI) in India to study the production of biodiesel from Jatropha curcas. It also has a 160 million joint venture with D1 Oils to develop the planting of Jatropha curcas. 

Genome sequence of Clostridium acetobutylicum GXAS18-1, a novel biobutanol production strain. Genome Announc., 3, e00033-15. 

Kuroda, K. and Ueda, M. (2016) Cellular and molecular engineering of yeast Saccharomyces cerevisiae for advanced biobutanol production. FEMS Microbiol Lett., 363, fnv247. 

Fermentative Biobutanol Production An Old Topic with Remarkable Recent Advances... 

The market demand is also essential for the economics of butanol fermentation. It is expected that after biobutanol is adapted as a liquid fuel, the demand will astonishingly increase. Nonetheless, butanol is even more important as a chemical feedstock rather than as a fuel (Mascal, 2012). So, development of novel feasible industry routes for butanol-derivative products could significantly increase the market demand for butanol, and thus draw closer to the commercial production of biobutanol using the biological fermentation process. Furthermore, the recovery and utilization of the fermentation by-products (nutritional waste stream, cell biomass, CO2, and H2) can also contribute substantially to the economics of biobutanol production. For example, H2 can be used as a clean energy source, while the nutritional waste stream and cell biomass can be used for some agricultural purposes after proper treatment processes. 

Although the commercial production of biobutanol through the traditional ABE fermentation process is not currently or in the near future economically viable, the policy makers should take account the tremendous credit from the reduction of waste and the green house gases due to the renewable production processes. More attention and investments on the basic research are needed, in order to advance the whole biobutanol production pipeline and make it ultimately commercially feasible in the near future. 

Kumar M, Gayen K. (2011). Developments in biobutanol production new insights. Appl Energy, 88, 1999-2012. 

Great effort has been invested in research on biobutanol production, which is in the last preparation stages for an industrial-scale process, with pilot plants being built around the world. Some of the main issues are still butanol toxicity, low strain productivity, low yield, incomplete substrate usage, inability to use cheap lignocellulosic feedstock and high separation costs. Many of these problems are caused by butanol toxicity. 

Biological production of isobutene from microbes is already known since the 1970s. However, meticulous metabolic engineering is essential to achieve economically feasible yields and productivities (van Leeuwen et al. 2012). This cmitrasts biobutanol production by Clostridia, where metabolic engineering to improve butanol tolerance and productivity is desirable, but it is theoretically possible to achieve economic viability by just improving substrate preparation and separation techniques. 

This is why a significant amount of research on biobutanol production has been made on the use of alternative fermentation and product recovery methods (Lee et al. 2008 Ezeji et al. 2007b). Some of these methods include, besides distillation. 

Table 1 The challenges and solutions of biobutanol production (Great 2011)...

When considering the knowledge base of biobutanol production, enormous amounts of time and effort have already been invested into research and development, there is an abtmdance of scientific and industrial resources, and there already are production plants in place, while sustainable industrial-scale production is plausible in the foreseeable future. On the other hand, research and know-how on industrial bio-isobutene production is practically stiU in its infancy. 

Chen, B.-Y., Chuang, F.-Y., lin, C.-L., Chang, J.-S., 2012. Deciphering butanol inhibition to Clostridial spedes in acclimatized sludge for improving biobutanol production. Biochemical Engineering Jotimal 69,100-105. 

Wang, Y., Janssen, H., Blaschek, H.P., 2014. Fermentative biobutanol production an old topic with remarkable recent advances. Bioprocessing of Renewable Resources to Commodity Bioproducts 227—260. 

A hybrid process that combines membrane separation and distillation for bioethanol and biobutanol production is being worked on by MTR [88, 89]. The membrane units use either vapor permeation or PV. The BioSep processes offer more than 50% energy savings and are cost competitive with respect to conventional distillation-molecular sieve technology. They are attractive when the ethanol concentration in the fermentation step is low, such as in cellulose-to-ethanol and algae-to-ethanol. In the case of biobutanol production, the membrane systems concentrate and dehydrate the acetone, butanol and ethanol mixture, saving up to 87% of the energy required to recover biobutanol by conventional separation techniques. 

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