Recent advancements in various steps of ethanol, butanol, and isobutanol productions from woody materials

Chemical Engineering Department, Lakehead University, Thunder Bay, ON, Canada, P7B5E1. .
Biotechnology Progress (Impact Factor: 2.15). 03/2013; 29(2). DOI: 10.1002/btpr.1688
Source: PubMed


In this review, the recent advancements and technical challenges associated with the production of ethanol, butanol and isobutanol via bioconversion routes from celluloses of woody materials are reviewed. Physicochemical processes, e.g. steam explosion, seem to be the most viableprocessfor pretreating woody materials. Although enzymatic hydrolysis is selective, it is rather a slow process. Acid hydrolysis is a relatively fast process with a high yield, but it produces inhibitory compounds of fermentation, which necessitates a detoxification process prior to the fermentation. Presently, the major challenges in the production of ethanol,butanol and isobutanol via biological conversions are the ratherlow production yield and the sensitivity of microorganisms to the presence of inhibitors and productsin fermentation media. In this study, the recent advancements in the applications of S. cerevisiae,C. Acetobutylicum and C. glutamicumas, the most promising microorganisms, for ethanol, butanol and isobutanol production arealso discussed. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 2013.

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    • "The gradual adsorptions of lignin and hemicelluloses may be due to their diffusion into the AC pores, as diffusion is a slow process (Fatehi et al., 2011; Lashaki et al., 2012). These results are well in harmony with previously reported results on the adsorption of lignin and hemicelluloses of pre-hydrolysis liquor (PHL) on activated carbon and precipitated calcium carbonate (Fatehi et al., 2013a,b). 3.5. "
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    • "Butanol is a product of ABE (acetone butanol ethanol) fermentation (Gottschalk 1986), and it represents an excellent chemical feedstock (in the plastics industry), and more importantly, a superior fuel compared to ethanol (Pfromm et al. 2010), since it is less corrosive, less hygroscopic, and tolerates water contamination better; it is less evaporative and explosive due to its lower vapor pressure; it has 30 % higher energy density than ethanol; it can be mixed in higher ratios with gasoline in existing cars without retrofitting the engine (Fatehi 2013). Butanol can be produced by a variety of microorganisms and the most commonly used strains are Clostridium acetobutylicum and Clostridium beijerinckii (Durre 1998; Qureshi et al. 2006). "
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