Biobutanol: science, engineering, and economics

Abstract

SUMMARYAmong several liquid alternative fuels, biobutanol has shown great promise because of its very similar properties to gasoline. This review provides an overview of research activities in acetone-butanol-ethanol (ABE) fermentation over the past two and a half decades. We have addressed seven important facets of ABE fermentation, viz. biochemistry, microbial cultures, alternative substrates, solvent recovery, fermentation mode and reactor designs, mathematical modeling, and economics. Development of mutant strains having higher yield, selectivity and tolerance to inhibition, and search for cheap alternative substrates for fermentation are most important thrust areas in biobutanol production. New and efficient processes have been developed for in situ removal and recovery of the ABE solvents. Several rigorous kinetic and physiological models for fermentation have been formulated, which form useful tool for optimization of the process. These research activities have been reviewed in this paper. Finally, we have summarized studies on the economic viability of large-scale ABE fermentation processes employing various process designs, substrates, and microbial cultures. With the use of new strains, inexpensive substrates, and superior reactor designs, economic potential of ABE fermentation has been found to be highly attractive. Research efforts in science, engineering, and economics of ABE fermentation have brought biobutanol close to commercialization as liquid alternate fuel.

Material compatibility evaluation for elastomers, plastics, and metals exposed to ethanol and butanol blends

“…Recently, the use of genetically enhanced bacteria has increased the productivity of fermentation process. It is expected that sustainable and cost effective process for butanol production will be realized in the near future [7,8].…”

Biobutanol: the outlook of an academic and industrialist

“…The current international price of bulk grade butanol is approximately $4 per gallon (liquid fuels) with a worldwide market of 350 million gallons per year. 6 The conventional chemical processes for butanol synthesis includes the oxo process, wherein synthesis gas is reacted with propylene and hydrogenated subsequently to produce butanol. Table 1 lists and compares some common properties of various alternative liquid fuels.…”

Can Microbially Derived Advanced Biofuels Ever Compete with Conventional Bioethanol? A Critical Review

“…Bacterial contamination and consequent impact on the solvent production prompted the closure of many ABE fermentation plants in 1920s (Ross 1961). However, at the end of World War II, two-thirds of butanol and one-tenth of acetone production in the Unites States were from fermentation processes (Ross 1961;Ranjan and Moholkar 2012).…”