Gasoline oxygenates ethanol

Oxygenate Ethanol, methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME) these components improve the octane number and help lower the CO and exhaust HC emission level of gasoline. 

Some compounds, such as alcohols, are made of carbon, hydrogen, and oxygen. In the combustion of these compounds, carbon dioxide and water are still made. For example, the fuel known as gasohol is a mixture of gasoline and ethanol, an alcohol. The balanced chemical equation for the combustion of ethanol is shown below. 

Because of the adverse effects of MTBE, ethanol is now considered as a promising alternative oxygenate. Ethanol is now marketed and distributed in every state in the United States. Ethanol is safe, biodegradable, and renewable. It also does not harm drinking water resources. Currently, around 80% of gasoline in California is blended with ethanol. At this time, the total ethanol consumption in California is 950 million... 

Properties Amber pellets insol. in water misc. with ethanol, acetone, benzene, monochlorobenzene, isopropyl acetate, gasoline, oxygenated and aromatic soivs. dens. 1.08 soften, pt. 75 C m.p. 95-100 C Toxicology TDLo (oral, rat) 548 g/kg experimental neoplastigen questionable carcinogen TSCA listed... 

Consider ethyl-tertiary-butyl-ether (ETBE) as an alternative gasoline oxygenate to MTBE. While the latter appears to have the best combination of properties such as oxygen content, octane number, energy content, and cost, the former can be manufactured using ethanol according to ... 

Outside of hydrocarbons, certain organic oxygenated compounds such as the alcohols and ethers are henceforth utilized in the formulation of gasolines. These are mostly methanol, ethanol, propanols and butanols, as well as methyl and ethyl ethers obtained from and Cj olefins ... 

Sasol Fischer-Tropsch Process. 1-Propanol is one of the products from Sasol s Fischer-Tropsch process (7). Coal (qv) is gasified ia Lurgi reactors to produce synthesis gas (H2/CO). After separation from gas Hquids and purification, the synthesis gas is fed iato the Sasol Synthol plant where it is entrained with a powdered iron-based catalyst within the fluid-bed reactors. The exothermic Fischer-Tropsch reaction produces a mixture of hydrocarbons (qv) and oxygenates. The condensation products from the process consist of hydrocarbon Hquids and an aqueous stream that contains a mixture of ketones (qv) and alcohols. The ketones and alcohols are recovered and most of the alcohols are used for the blending of high octane gasoline. Some of the alcohol streams are further purified by distillation to yield pure 1-propanol and ethanol ia a multiunit plant, which has a total capacity of 25,000-30,000 t/yr (see Coal conversion processes, gasification). 

Demand for gasoline is 125 billion gals (473 billion 1) per year according to 1998 estimates. The Clean Air Act Amendment of 1990 mandates the use of oxygenated fuels such as ethanol blends with up to 3.5 percent oxygen by weight in gasoline (E-10 or... 

In the late 1990s, MTBE came under serious attack on grounds of both efficacy and safety. A report by the National Research Council (1999) stated that the addition of oxygen additives in gasoline, including MTBE and ethanol, are far less important in controlling pollution than emission control equipment and technical improvement to vehicle engines and exhaust systems. 

Ethanol, CH3CH2OH, is produced from the biological fermentation of the starches in grains, mainly corn. It currently makes up about 10% by volume of gasoline in the United States, thereby reducing pollution as well as the use of petroleum. The oxygen atom in the ethanol molecule reduces emissions of carbon monoxide and hydrocarbons by helping to ensure complete combustion. One bushel of... 

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