Question

Explain the preparation of ethyl alcohol from molasses?

Answer 1

Hint: Try to recall that ethanol is manufactured by the fermentation of grain and fruit containing sugar and starch. Also, molasses to ethanol or ethyl alcohol processes are commercial and exclusively used in India. Now, by using this you can easily answer the given question.

Complete step by step solution:
It is known to you that ethanol is a renewable source of energy and a dependable alternative to fossil fuels and its demand enhances with time for versatile applications.
In industries, ethanol is prepared from molasses. Molasses are residues when sugar cane is processed while producing sugar from it.
Ethanol production processes from molasses takes place in three steps:
i) Dilution of molasses: In this step, water and enzymes are added for the conversion of molasses into fermentable sugar.
ii) Fermentation: In this step, the mash is fermented using yeast, whereby the sugar is converted into ethanol and carbon dioxide.
iii) Distillation and rectification: In this step, concentration and cleaning of ethanol produced by distillation takes place.
Drying: In this last step, dehydration of ethanol takes place.
The fermentation reaction of ethyl alcohol from molasses is as follows:
\[
  {C_{12}}{H_{22}}{O_{11}} + {H_2}O \to {C_6}{H_{12}}{O_6} + {C_6}{H_{12}}{O_6} \\
  {C_6}{H_{12}}{O_6} \to {C_2}{H_5}OH + C{O_2} \\
\]
During fermentation, first sucrose is converted into glucose and fructose by enzyme invertase and then glucose is converted into ethyl alcohol.

Note: It should be remembered to you that ethanol is more or less carbon neutral fuel that is produced from a fixed carbon-dioxide.
Also, you should remember that ethanol is used for the preparation of alcoholic beverages like whisky, rum, brandy, gin etc.