Biofuel production butanol

The production of biofuels (ethanol, butanol and biodiesel) falls into two categories ... 

Eischer CR, Klem-Marcuschamer D, Stephanopoulos G (2008) Selection and optimization of microbial hosts for biofuels production. Metab Eng 10(6) 295-304 Eontaine L et al (2002) Molecular characterization and transcriptional analysis of adhE2, the gene encoding the NADH-dependent aldehyde/alcohol dehydrogenase responsible for butanol production in alcohologenic cultures of Clostridium acetobutylicum ATCC 824. J Bacteriol 184 (3) 821-30... 

Many of the existing energy products are being used as fuel for the transport sector and are made from either petrol-based material or from renewable resources such as biomass by some kind of chemical process. The most common biofuels that are being used for transport purposes are dimethyl ether (DME), methanol, ethanol, butanol and biodiesel. 

Figure 2.1.2 Selected biomass-derived platform chemicals that have been demonstrated to be feedstocks for the production of potential biofuels (EtOH, ethanol BuOH, butanol).

Dusseaux, S., Croux, C., Soucaille, P., and Meynial-Salles, I. (2013) Metabolic engineering of Clostridium acetobutylicum ATCC 824 for the high-yield production of a biofuel composed of an isopropanol/butanol/ethanol mixture. Metab. Eng., 18, 1-8. 

Just as the fossil fuel and petrochemicals industries are closely connected, the production of the same but bio-based chemicals will be closely related to the manufacturing of biofuels. The focus of commercialization by using biomass as a feedstock is mainly on ethanol, biodiesel, butanol, hydrogen, Fischer-Tropsch fuels, methanol, methane, and MTBEyETBE (methyl- or ethyl-tert-butylether). These products can be used either as biofuels or chemicals for further converting. In the context of this chapter, only routes for the ethylene and propylene... 

The development of PH A into a branch of bulk chemical industry will address at least three issues shortage of petroleum for plastic materials, reduction of CO emissions, and environmental protection. It is related to the sustainable development of the chemical and material industries. The newly developed PHA-based biofuels open up a new area for development that avoids argument on food versus fuel and fuel versus land. However, much more work needs to be done to reduce the cost of PHA production so that PHA-based biofuel can be added to the existing bio-based fuels, including ethanol, propanol, butanol, biodiesel, hydrogen, and methane gas (Fig. 7). 

Clostridium acetobutylicum Acetone-butanol-ethanol (ABE) Algal biomass was converted into biofuel. Different algal species gave different product profiles [6]... 

Economic studies on the production of biobutanol from corn determined that distillation recovery of butanol from the dilute ABE fermentation broth is not economical comparing to the butanol production from the current petrochemical route (Ezeji et al., 2007c). However, the life-cycle analysis on the corn-based butanol production indicated that the use of corn-based butanol as a biofuel can lead to substantial fossil energy savings relative to the use of conventional petroleum gasoline, and it can also avoid a large amount of GHG emission burdens (Wu et al., 2008). 

Butalco 2007 Canton of Zug, Switzerland Based on genetically optimized yeasts for production of advanced biofuels like ethanol and butanol by using pentose sugars Working together with partners to develop integrated production processes (Butalco.com, 2012)... 

Alsaker KV, Paredes C, Papoutsakis ET. (2010). Metabolite stress and tolerance in the production of biofuels and chemicals gene-expression-based systems analysis of butanol, butyrate, and acetate stresses in the anaerobe Clostridium acetobutylicum. Biotechnol Bioeng, 105, 1131-1147. 

The interest in w-butanol as a biofuel has increased in recent years owing to its superior fuel qualities compared to ethanol. These include a higher octane number, lower heat of vaporization, higher energy density (energy/volume), and lower vapor pressure. However, in the traditional ABE (acetone-butanol-ethanol) fermentation process, the concentration of n-butanol coming from the fermenter is lower than that achieved in ethanol fermentation. In addition, acetone and ethanol are also produced. Recent studies to improve yield and increase w-butanol concentration have explored fed-batch systems with stripping, adsorption, liquid-liquid extraction, distillation, and/or pervaporation to recover products. 

The emerging biofuel processes typically have fermentation products that form azeotropes with flie water, which is present in large excess in the fermentor. The most important example is ethanol, which forms a minimum-boiling homogeneous binary azeotrope with water. Butanol is anoflier biofuel example that forms an azeotrope with water. The nonideality in this system is so large that the azeotrope is heterogeneous, forming two liquid phases. 

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