To produce ethanol

Although the hydrolysis of wood to produce simple sugars has not proved to be economically feasible, by-product sugars from sulfite pulping are used to produce ethanol and to feed yeast (107). Furthermore, a hemiceUulose molasses, obtained as a by-product in hardboard manufacture, can be used in catde feeds instead of blackstrap molasses (108). Furfural can be produced from a variety of wood processing byproducts, such as spent sulfite Hquor, bquors from the prehydrolysis of wood for kraft pulping, hardboard plants, and hardwood wastes (109). 

Oxidation of Hydrocarbons. Ethanol is one of a variety of oxygen-containing compounds produced by the oxidation of hydrocarbons. Ethanol is reported to be obtained in a yield of 51% by the slow combustion of ethane (158,159). When propane is oxidi2ed at 350°C under a pressure of 17.2 MPa (170 atm) (160,161), 8% of the oxygen is converted to ethanol. Lower conversions to ethanol are obtained by oxidi2ing butane. Other oxidation systems used to produce ethanol and acetaldehyde (162—164) and methods for separating the products have been described in the patent Hterature. 

Corn can be used to produce ethanol. (U.S. Department of Energy)... 

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... 

Alcoholic fermentation, ethanol production, has been best known for a few decades by S. cerevisiae. Many obligate aerobic fungi, such as common moulds of the genera Aspergillus, Fusarium and Mucor are also well known for their ability to produce ethanol.2 The benefits are ... 

A scientist proposed the following two reactions to produce ethanol, a liquid fuel ... 

Although the use of fermentation to produce ethanol is an ancient technology, more efficient immobilized-cell, continuous processes have been conceived, and Japan has estabhshed the first demonstration-scale plant. 

Once the product specifications have been fixed, some decisions need to be made regarding the reaction path. There are sometimes different paths to the same product. For example, suppose ethanol is to be manufactured. Ethylene could be used as a raw material and reacted with water to produce ethanol. An alternative would be to start with methanol as a raw material and react it with synthesis gas (a mixture of carbon monoxide and hydrogen) to produce the same product. These two paths employ chemical reactor technology. A third path could employ a biochemical reaction (or fermentation) that exploits the metabolic processes of microorganisms in a biochemical reactor. Ethanol could therefore also be manufactured by fermentation of a carbohydrate. 

Fischer-Tropsch reaction of CO/H2 to produce ethanol followed by the Sasol Kvaemer process. 

All fungi capable of producing kojic acid were known to produce ethanol at the same time. Hence, acetaldehyde would also have to be present in the... 

Countries that have plenty of oil reserves, and are relatively rich, use the hydration method to produce ethanol, whereas those with a warm climate (where sugar can easily grow) and that are relatively poor, with no oil reserves, are more likely to use the fermentation method. In addition to its use in alcoholic beverages (fermentation method), ethanol is used industrially both as a fuel and as a solvent. 

Ethyl acetate (A) reacts with OH- (B) to produce ethanol and acetate ion The reaction is... 

When agricultural surplus was used for the production of ethanol in the United States, it provided economic benefits to farmers and to the farming economy. In 1990, almost 360 million bushels of surplus grain were used to produce ethanol. In that year, it is estimated that ethanol production increased farm income by 750 million while federal farm program costs dropped by 600 million and crude oil imports fell by over forty million barrels. 

In 2007 a bumper crop in corn took the edge off problems with supplies. The USDA confirmed that corn acreage was up almost 20% from 2006, with farmers planting almost 2.5 million more acres than they had planned. The crop was estimated at 13 billion bushels, up 23% from 2006. This caused corn prices to drop 40 cents to 50 cents a bushel, but increasing demand for corn to produce ethanol and to feed livestock in Asia, Latin American and elsewhere kept world stocks low. 

A pilot plant using residual straw as feedstock to produce ethanol is in operation by Iogen in Ottawa, Canada. The plant can produce up to 3000 m3 of ethanol annually (Iogen, 2005). 

A) Ethanol reacts with hydrochloric acid to produce chloroethane. (B) In a basic solution, tbe reverse reaction takes place. A hydroxide ion reacts with chloroethane to produce ethanol. 

Other organisms are equipped to produce ethanol, by employing a thiamine diphosphate-dependent decarboxylation of pyruvate to acetaldehyde (see Section 15.8) and NAD+ is regenerated by reducing the acetaldehyde to ethanol. This is a characteristic of baker s yeast, and forms the essential process for both bread making (production of CO2) and the brewing industry (formation of ethanol). 

Warren, R.K., Hill, G.A. and Macdonald, D.G., Continuous cell recycle fermentation to produce ethanol. Food Bioprod. Proc., 72 (1994) 149-157. 

This is the most economical process to produce ethanol, but laws prohibit drinking synthetic ethanol so beverages are made much more expensively by fermentation of sugar or carbohydrates. Recent laws also mandate the addition of 10% ethanol in gasoline in cities during the winter, supposedly to reduce pollution. However, grain processors lobbied to require renewable resources so fermentation is required to produce this fuel alcohol. 

This type of autocatalytic reaction is a simplification of many biological reactions such as fermentation, where the reaction produces products (species B in the previous example), which accelerates the rate. In fermentation, yeast cells in the solution produce enzymes that catalyze the decomposition of sugar to produce ethanol as a byproduct of yeast reproduction. Since the yeast population increases as the reaction proceeds, the enzyme concentration increases, and the process appears to be autocatalytic. A highly simplified description of fermentation might be... 

Some whey has found alternative applications, such as fermentation to produce ethanol. 

By-products of starch refining and HFCS prodnction are significant and rednce HFCS production costs by 30 5% (Table 4.2). This is because the com is 70% starch on a dry weight basis, it also contains 10% protein, 4.5% fat and 2.7% erode fibre. In addition much of the glucose syrup produced is fermented to produce ethanol for fuel use. 

An additional feature is that the glucose syrups can also be fermented to produce ethanol for use in fuels. Obviously HFCS is a more valuable product, but power ethanol production does generate significant revenues. 

Iodide-promoted reactions in phosphine oxide solvents have been observed under some conditions to produce ethanol from H2/CO with good rates and high selectivities (193-195) (Table XVI, Expts. 1-3). Experimental evidence suggests that the ethanol is a secondary product, although its selectivity is high even after very short reaction times (193). An acid component is believed to be involved in alcohol homologation by this system, which will be described in more detail below. 

Figure 15.8 Fermenting glucose and yeast to produce ethanol. The bag is inflated during the experiment by C02.

In addition to creating bio-oil from algae, it is also possible to produce ethanol. Whilst the aerobic fermentation of sugars to produce alcohol has been recognized... 

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