When we arrive at a refueling station, it is common to see on information boards or on the fuel pump itself the word ethanol. This means that the vast majority of people are aware that this compound is a fuel. Ethanol it's a liquid colorless that belongs to a group of substances known as alcohols. For that reason, he is commonly called alcohol.
We can also find this liquid in supermarkets or pharmacies in 1L or 500 mL bottles, for example, and use it for general cleaning. Interestingly, the composition of alcohol in supermarkets and drugstores is different from the composition of ethanol found at gas stations.
Thus, it is a fact that we know many functions of this colorless liquid so known and used daily. But do you know its specific characteristics and how it is produced? Through this text, you can become a real connoisseur of ethanol. Shall we start then?
Ethanol is not alcohol, but an example of alcohol, since, cOm any and all alcohol, ethanol, in addition to chemical elements such as carbon, hydrogen and oxygen, has in its structure a group called hydroxyl (OH), which necessarily makes a chemical bond with a carbon, as represented in formula a follow:
General chemical structure of an alcohol
In it we can see that the OH group is on a carbon (C) that performs only the so-called single bonds, an aspect that characterizes this carbon as saturated.
Ethanol has the following main characteristics:
It's liquid;
It is colorless;
It has a characteristic odor (everyone knows the smell of alcohol!);
It dissolves very well in water;
It is flammable (combustible);
It has a boiling point of 78.4 OC (evaporates faster than water);
It has a melting point of -114.13 OC (does not freeze in the freezer or domestic freezer);
Its formula is:
Chemical structure of ethanol
Its production involves several important steps, but first let's know from which products alcohol can be produced. Are they:
Sugarcane (simpler and more productive);
Corn;
Beetroot;
Potato;
Wheat;
Cassava.
Sugarcane is a product used to produce ethanol
The processes that involve the production of ethanol are:
a) Harvesting, washing and cutting:Sugarcane is harvested from the plantation and sent to the production plants. Arriving at the plant, it is washed to remove all impurities and then cut into smaller pieces.
b) Magnetization:an electromagnet is passed through the pieces of cane to remove metals.
c) Grinding:The pieces of cane go through compressor rollers, which crush them to remove their juice. This broth is called molasses.
d) Sieving:At this stage, the molasses goes through a sieve to remove any remaining bagasse that may have remained after it was crushed.
e) Decantation:After sieving, the molasses is left to rest in a tank so that the impurities that did not come out with the sieving go down to the bottom of the container.
f) Heating: The molasses removed from the tank without impurities undergoes heating to kill all microorganisms (bacteria and fungi).
g) Fermentation:The molasses is placed in a tank and given a quantity of biological yeast (fungi). They feed on sugar and transform it into ethanol and carbon dioxide (CO2). The fermented liquid is called vinasse.
h) Distillation:The vinasse is heated, and its liquid components go into a vapor state and, shortly thereafter, undergo condensation (return to a liquid state). At this stage, ethanol and water, hydrated alcohol, are separated from the vinasse.
Note: A part of the hydrated alcohol is stored and another part goes through the dehydration process.
f) Dehydration:It is the step that removes water from the hydrated alcohol obtained in the distillation, forming anhydrous alcohol.
g) Storage:Hydrous ethanol and anhydrous ethanol are deposited in large tanks.
Ready! You are now ready to inform your relatives and friends about ethanol. Good conversation!
By Me. Diogo Lopes Dias
