Ethanol fuel additive

In the first years of gasohol use some starting and driveabiUty problems were reported (19). Not all vehicles experienced these problems, however, and better fuel economy was often indicated even though the energy content of the fuel was reduced. Gasohol was exempted from the federal excise tax amounting to a 0.16/L ( 0.60/gal) subsidy. Without this subsidy, ethanol would be too expensive for use even as a fuel additive. 

Some isopentane is dehydrogenated to isoamylene and converted, by processes analogous to those which produce methyl /-butyl ether [1634-04-4] (MTBE) to /-amyl methyl ether [994-05-8] (TAME), which is used as a fuel octane enhancer like MTBE. The amount of TAME which the market can absorb depends mostly on its price relative to MTBE, ethyl /-butyl ether [637-92-3] (ETBE), and ethanol, the other important oxygenated fuel additives. 

The chemical formula for ethanol is Cl L,Cl TOIL Ethanol is less toxic and more biodegradable than gasoline. For its octane boosting capability ethanol can be use as a fuel additive when blended with gasoline. 

United States, methanol derived from natural gas as a fuel additive is a promising future market. Methanol has neither the environmental problems of methyl-t-butyl ether (MTBE), nor the evaporating qualities of ethanol. 

The enzyme is also being studied for use in converting of biomass to ethanol for fuel usage. Prospects for the conversion of cellulolytic biomass to ethanol for fuel or as a fuel additive have improved within the last decade because of the development of methods for the fermentation of xylose, which can comprise as much as 50% of the fermentable sugars in these feedstocks. One of these methods uses xylose isomerase to convert xylose, which is difficult to ferment by ethanol-tolerant yeasts, to the fermentable sugar xylulose (12,13). 

Glucose syrups are easily fermented by yeast to ethanol. While beverage ethanol has been produced from many sources of sugar and starch for countless centuries, large-scale production of fuel-grade ethanol by fermentation is attributed to a demand for combustible motor fuel additives. 

Blends of ethanol with diesel are a valuable car fuel too. The formation of NO is drastically reduced even by small amounts of ethanol. In addition, the temperatures of the exhaust gas and lubricating oil are lower, while the engine can be started normally both hot and cold. 

There are over 70 alcohols in the atmosphere as a result of biogenic and anthropogenic emissions [67]. For example methanol and ethanol [68-70] have been used as fuels additives to reduce automobile emissions of carbon monoxide and hydrocarbons [71], in particular ethanol has been used in Brazil as a fuel for over 20 years [72]. 1-Propanol is widely used as a solvent in the manufacturing of different electronic components. The high volatility of these compounds causes their relative abundance in the troposphere and makes it relevant to determine their degradation pathways. During daytime the major loss process for alcohols is their reaction with OH radicals [68]. Accordingly, several experimental [69,70,73-84] and theoretical [85-88] kinetic studies of alcohols -F OH reactions have been performed. 

A recent experiment in a laboratory MHD channel at Stanford ( ) has shown that, under MHD conditions (high potassium loading), the addition of phosphorus, even in amounts much greater than those found in coal, has a much smaller effect on electron concentration and conductivity than would be predicted by the above modeling. That experiment Involved simultaneous measurement of electron concentration by submillimeter interferometry, of positive ion concentration by a swept electric probe, and of plasma temperature by the emission-absorption (line-reversal) technique, made in an ethanol-fueled, potassium-seeded combustion plasma. 

Energy Ethanol from carbohydrates and methane from organic waste Fuel additives or heat generation... 

Neat methanol and ethanol fuels do not present the problem of phase separation since water is soluble in these alcohols in all proportions except at very low temperatures. Interestingly, it is not necessary to use anhydrous neat alcohol fuels in spark-ignition engines. The neat ethanol-fueled automobiles in Brazil operate with 190 proof ethanol (95 vol %), which precludes the energy-consuming step of producing anhydrous ethanol. Indeed, the addition of 10 and 20 wt % water to methanol raises its octane value to about 107 and... 

Chronic ethanol exposure by ingestion of alcoholic beverages produces widespread toxicity, ranging from liver and nervous system damage to reproductive impairment and birth defects. People are not likely to be exposed orally to ethanol alone when used as a fuel additive, and systemic effects of chronic exposure to ethanol by respiratory and dermal uptake would be negligible. 

The addition of ethanol to gasoline reduces harmful vehicle emissions and facilitates the reduction or removal of toxic air components, which are commonly found additives in gasoline. Emissions of carbon dioxide (CO2), the primary greenhouse gas contributing to global warming, have increased steadily, and the transportation sector alone accounts for 33% of total emissions. It is estimated that an 85% ethanol fuel would reduce greenhouse gas emissions between 15%i and Ethanol-blended fuels would reduce... 

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