ethanolC2H4(g) + H2O(l)
C2H5OH(l)gcsescience.com 42 gcsescience.com
Ethanol - Properties and Formation.
Ethanol is an alcohol with the molecular formula C2H5OH
(see also the
structural
formula).
Ethanol is not a hydrocarbon because the molecule contains oxygen
as well as hydrogen and carbon.
Ethanol is a colourless
liquid which boils at
78 °C.
It is completely miscible with water.
This means that it mixes with water
in any quantity.
Ethanol is a neutral liquid.
Ethanol can be made
by the fermentation of a sugar
solution (batch process)
or buy the reaction of ethene with steam
in the presence of phosphoric acid
(continuous process).
A continuous process means that
reactants are
constantly being put in
at one
end of the reaction vessel and
products
are
constantly being taken out at the
other end of the reaction
vessel.
Adding the components of water
across the double bond of ethene is
called the hydration of ethene.
The reaction is carried out at a
high temperature and a high pressure.
ethene
+ steam
ethanol
C2H4(g)
+ H2O(l)
C2H5OH(l)
See a comparison of the batch process with the continuous process below.
| Process | Batch Process | Continuous Process |
| Reaction | Fermentation | Hydration of Ethene |
| Renewable Resource? | Yes - Sugar Cane | No - Crude Oil |
| Rate of Reaction | Slow | Fast |
| Product | Ethanol / Water mixture | Pure Ethanol |
Industry would rather use the continuous process than the batch process
because of the fast production of a
pure product. In some countries
it may be more practical to use the
batch process - see next page.
Headings Ethanol Search Questions 
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Copyright © 2008 Dr. Colin France. All Rights Reserved.