Energy sources ethanol

Excise taxes placed on specific energy sources tend to reduce the demand for these energy sources in both the short and the long run. The federal government imposes excise taxes on almost all petroleum products and coal (see Table I). The federal government also imposes excise taxes on many transportation uses of methanol, ethanol, natural gas, and propane and imposes a fee on electricity produced from nuclear power plants. 

Owing to diminishing fossil fuel reserves, alternative energy sources need to be renewable, sustainable, efficient, cost-effective, convenient and safe.1 In recent decades, microbial production of ethanol has been considered as an alternative fuel for the future because fossil fuels are depleting. Several microorganisms, including Clostridium sp. and yeast, the well-known ethanol producers Saccharomyces cerevisiae and Zymomonas mobilis, are suitable candidates to produce ethanol.2,3... 

Wood chips can also be utilized as such to produce bioethanol. The cellulose and hemicellulose material is hydrolyzed in the presence of acids (H2SO4, HCl, or HCOOH) or enzymes to yield glucose and other monosaccharides [16]. Lignin is separated by filtration as a solid residue and the monosaccharides are fermented to ethanol, which, in turn, is separated from water and catalyst by distillation. Ethanol can be used not only as energy source but also as a platform component to make various chemicals, such as ethene and polyethene. Today green acetaldehyde and acetic acid from wood-derived bioethanol is manufactured by SEKAB Ab, at the Ornskoldsvik Biorefinery of the Future industrial park. 

Solubility/miscibility Slightly soluble in ethanol miscible with ether Biological considerations Can serve as an energy source Chemical compatibility/Stability considerations Pale yellow or light greenish-yellow oil. Becomes rancid upon exposure to air Uses (routes) Oral... 

Solubility/miscibility Miscible with ether and other oils. Slightly soluble in ethanol slightly soluble in ether Biological considerations Orally, serves as an energy source Chemical compatibility/Stability considerations Clouds at room temperatures. 

Today ethanol and biodiesel (FAME) are the most common biofuels. Alternative fuels from fossil energy sources are mainly LPG and CNG. Synthetic gasoline and diesel from coal (CTL) and natural gas (GTL) are produced mainly in South Africa. Electricity used in battery-electric vehicles plays a minor role today. The fuel consumption for road transport in the world today amounts to about 65 700 PJ per year (IEA, 2006a) in total, the share of alternative fuels for transport at the time of writing was about 2.7% (Table 7.24). 

Alcohol is a clean energy source that can be produced by the fermentation of biomass. However, it needs to be highly concentrated. In general, aqueous alcohol solutions are concentrated by distillation, but an azeotrope (96.5 wt% ethanol) prevents further separated by distillation. Pervaporation, a membrane separation technique, can be used for separation of these azeotropes pervaporation is a promising membrane technique for the separation of organic liquid mixtures such as azeotropic mixtures [34] or close-boiling point mixtures. 

Among theses energy sources Bio-diesel and ethanol have experienced impressive development in recent years, positioning these products in the market as an ecological alternative to the oil crisis. Unfortunately, Bio-diesel and ethanol are food-based... 

Alternative fuels can be used to power a fuel cell such as hydrogen, methane, natural gas, methanol, ethanol, liquehed petroleum gas and landfill gas, which can be produced from renewable energy sources such as biomass and wind. 

Kometani et al. [71] reported that baker s yeast catalyzed the asymmetric reduction of acetol to (i )-1,2-propanediol with ethanol as the energy source. The enzyme involved in the reaction was an NADH-dependent reductase, and NADH required for the reduction was supplied by ethanol oxidizing enzyme(s) in the yeast. When washed cells of baker s yeast were incubated with 10 mg ml of acetol in an ethanol solution with aeration, (k)-1,2-propanediol was formed almost stoichiometrically with an optical purity of 98.2% e. e. 

The energy source, the materials from which the dispersing device and the detector are constructed must be appropriate for the range of wavelength scanned and as transparent as possible to the radiation. For UV measurements, the cells and optieal components are typically made of quartz and ethanol, hexane, water or dioxan are usually chosen as solvents. 

The NADH-forming activity described here is different from the classical malic enzyme activity found by London et al. (95) in Lacto-badUus casei. In their system, NADH is a major end product and detectable by spectrophotometry while lactic acid is only a minor product. L. casei uses malic acid as an energy source with carbon dioxide, acetate, and ethanol as the main fermentation products. The optimal pH... 

Inside the yeast cell the hexoses are converted principally to ethanol, carbon dioxide, and adenosinetriphosphate (ATP) with the liberation of waste heat. The ATP is an energy source in cell metabolism the ethanol and carbon dioxide diffuse across the cell wall to the exterior where the ethanol dissolves in the juice and the carbon dioxide bubbles... 

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