HYDROGEN
Hydrogen was identified in 1776 by Henry Cavendish (Scottish chemist and physicist, 1731–1810), who called it “inflammable air” because of its high inflammability.
The name “hydrogen” is due to Antoine Lavoisier (French chemist, 1743–1794), who combined the words “hydro: water” and “genes: to generate”.
Hydrogen is a gas which, at ambient temperature (298K) and at atmospheric pressure, is colourless, odourless, tasteless, highly inflammable and light (atomic weight 1).
Hydrogen is the lightest and the most plentiful element all over the world. It is present in the water and in all the organic compounds and living organisms. Stars are mainly composed by hydrogen in a state of plasma.
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Extraction of hydrogen and oxygen through the hydrolysis
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THE PRODUCTION AND STORAGE OF HYDROGEN
Hydrogen is the fuel par excellence. In fact the reject of its combustion is steam so that the respect of the environment is maximum with the subsequent possible solution of problems related to the air pollution.
Unfortunately, hydrogen is not to be found in the natural state. However, it can be produced in various ways: from biomass, from waste through photo-electrochemical processes, from weeds through photo-biological reactions but above all through the electrolysis process from water.
This last extraction technique is very interesting if applied to the renewable energies.
In fact, if we think about the extraction of hydrogen in an industrial way from hydrocarbons, the respect of the environment by hydrogen is not realistic as for each carbon atom present in the hydrocarbons used in the reforming processes, a molecule of carbon dioxide is produced.
As we know, carbon dioxide is the main greenhouse gas, which cooperates to warm our planet with serious damages to the climate.
Indeed, the quantity of carbon dioxide obtained producing hydrogen through the reforming process is the same we would obtain if the methane or the oil were burnt directly in a power plant.
But the situation changes if the hydrogen is produced through water electrolyses using electrical energy produced by photovoltaic or wind systems. Then hydrogen is re-transformed into electrical energy using, for example, fuel cells .
Moreover, the electrolyses process produces, as excellent reject, oxygen too, which can be used for other important goals, increasing the system efficiency.
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