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Science

Polymers and ethanol from oil

Ethanol

Ethanol is the type of alcohol found in alcoholic drinks such as wine and beer. It is also useful as a fuel. For use in cars and other vehicles, it is usually mixed with petrol.

Structure of ethanol

formulachemical structureball-and-stick model
C2H5OHethanol has two carbon atoms, six hydrogen atoms and one oxygen atomthe carbon atoms are joined by a single bond

Ethanol from ethene and steam

Ethanol can be manufactured by reacting ethene (from crackingcracking: Cracking is the breaking down of large hydrocarbon molecules into smaller, more useful hydrocarbon molecules by vapourizing them and passing them over a hot catalyst. crude oil fractions) with steam. A catalystcatalyst: A catalyst changes the rate of a chemical reaction without being changed by the reaction itself. of phosphoric acid is used to ensure a fast reaction.

ethene + steam high temperature and high pressure goes to ethanol

C2H4+ H2O high temperature and high pressure goes to C2H5OH

Notice that ethanol is the only product. The process is continuous – as long as ethene and steam are fed into one end of the reaction vessel, ethanol will be produced. These features make it an efficient process, but there is a problem. Ethene is made from crude oil, which is a non-renewable resource. It cannot be replaced once it is used up and it will run out one day.

Back to Oils, Earth and atmosphere index

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