Uses of Alcohols
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This page briefly discusses some of the important uses of simple alcohols, such as methanol, ethanol and propan-2-ol.
The word "alcohol" in alcoholic drinks refers to ethanol (CH3CH2OH).
Industrial methylated spirits
Ethanol is usually sold as industrial methylated spirits, which is ethanol with a small quantity of methanol and possibly some color added. Because methanol is poisonous, industrial methylated spirits are unfit to drink, allowing purchasers to avoid the high taxes levied on alcoholic drinks.
Use of ethanol as a fuel
Ethanol burns to produce carbon dioxide and water, as shown in the equation below, and can be used as a fuel in its own right or in mixtures with petrol (gasoline). "Gasohol" is a petrol/ethanol mixture containing approximately 10–20% ethanol. Because ethanol can be produced by fermentation, this is a useful method for countries without an oil industry to reduce the amount of petrol imports.
\[CH_3CH_2OH +3O_2 \rightarrow 2CO_2 + 3H_2O\]
Ethanol as a solvent
Ethanol is widely used as a solvent. It is relatively safe and can be used to dissolve many organic compounds that are insoluble in water. It is used, for example, in many perfumes and cosmetics.
Methanol as a fuel
Methanol also burns to form carbon dioxide and water:
\[2CH_3OH +3O_2 \rightarrow 2CO_2 + 4H_2O\]
It can be used a a petrol additive to improve combustion, and its use as a fuel in its own right is under investigation.
Methanol as an industrial feedstock
Most methanol is used to make other compounds, for example, methanal (formaldehyde), ethanoic acid, and methyl esters of various acids. In most cases, these are then converted into further products.
Jim Clark (Chemguide.co.uk)