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An organic compound------ethanol

Ethanol, also known as ethyl alcohol or grain alcohol, is flammable, colorless chemical compound, one of the alcohols that are most often found in alcoholic drinks. Its chemical formula is C2H5OH, also written as C2H6O.

The chemical structures of ethanol’s symbols are: C is carbon, H is hydrogen and O is oxygen. The lines show what atoms are linked together by chemical bonds. An ethanol molecule mass is forty-six.

The uses of ethanol vary from drink to fuel. First of all, it is used a solvent because it can dissolve many other chemicals and is not very toxic. Also, it is most often used as a motor fuel, mainly as a befoul additive for gasoline. Otherwise, the alcohol is often as a drink.

There are two ways producing ethanol. During ethanol fermentation, glucose and other sugars in the corn (or sugarcane or other crops) are converted into ethanol and carbon dioxide.

Like any fermentation reaction, the fermentation is not 100% selective and other side products such acetic acid, glycols and many other products are formed to a considerable extent and need to be removed during the purification of the ethanol. The fermentation takes place in aqueous solution and the resulting solution after fermentation has an ethanol content of around 15%. The ethanol is subsequently isolated and purified by a combination of adsorption and distillation techniques. The purification is very energy intensive. During combustion ethanol reacts with oxygen to produce carbon dioxide, water, and heat:

C2H5OH + 3 O2 → 2 CO2 + 3 H2O + heat

Starch and cellulose molecules are strings of glucose molecules. It is also possible to generate ethanol out of cellulosic materials. That, however, requires a pretreatment that splits the cellulose into glycols molecules and other sugars that subsequently can be fermented. The resulting product is called cellulosic ethanol, indicating its source.

Ethanol may also be produced industrially from ethene (ethylene), by hydrolysis of the double bond in the presence of catalysts and high temperature.

C2H4 + H2O → C2H5OH

By far the largest fraction of the global ethanol production, however, is produced by fermentation