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Everyday new organic fuels that have not a fossil origin are developed for commercial proposes. Among these, the most promising for a close future are ethyl alcohol (ethanol), bioalcohol (which is a mixture of ethanol and methanol) and biogas (methane).
These organic fuels, as well as hydrogen, are the most promising fuels of the future.
The research in fuel chemistry has a straightforward goal of taking advantage of the use of these raw materials.
These organic fuels, as well as hydrogen, are the most promising fuels of the future.
The research in fuel chemistry has a straightforward goal of taking advantage of the use of these raw materials.
Ethanol (CH3CH2OH) is produced by biological fermentation of starches from cereals, particularly maize or from the sugar derived from sugar cane. This bioalcohol can then be purified to be almost entirely ethanol. Ethanol and methanol have oxygen in their molecular composition which reduces the energy released in the combustion of each molecule. However, they have a great tendency to burn without formation of secondary products which gives them better fuel characteristics concerning environmental protection. Since its combustion is total there is not a big energetic deficit when compared to hydrocarbons of similar molecular weight. The ethanol is denser that the methane will also carry greater weight in the same volume.
Cereals can be used do produce bioalcohol (Image credit: Wikipedia)
Methane (CH4) is also obtained from biological materials, but through anaerobic digestion, that is, by processes that occur in the absence of oxygen. Because it produces less energy than the ethanol per unit of volume, methane is less suitable as a fuel for vehicles of heavy transportation. However, it can be used in all applications where natural gas is used. For instance in many farms, suinicultures or herding, the biogas produced from the solid waste is used to feed electrically to the farm.
Another alternative fuel is biodiesel that can be produced from vegetable oils, such as peanut oil or soybean oil.
Hydrogen is the most abundant element in the universe. This makes scientists believe it will be the fuel of the future because it could hold the key to ongoing energy demands. Relatively new technologies (such as fuel cells) can be used to efficiently harness the chemical energy stored in diatomic hydrogen (H2). However, there is no accessible natural reserve of uncombined hydrogen, since what little there is resides in Earth's outer atmosphere (exosphere). Hydrogen for use as fuel must first be produced using another energy source; hydrogen would thus actually be a means to transport energy, rather than an energy source, just as common rechargeable batteries are. One existing method of hydrogen production is steam methane reformation; however, the most common source of methane is natural gas, which is in short supply. Another method of hydrogen production is through electrolysis of water which uses electricity generated from any source like renewable energy sources (solar, eolic, etc). If molecular hydrogen could be obtained from the water in an economically viable way it would be a virtually inexhaustible source because its combustion regenerates it back to water.
Hydrogen is the most abundant element in the universe. This makes scientists believe it will be the fuel of the future because it could hold the key to ongoing energy demands. Relatively new technologies (such as fuel cells) can be used to efficiently harness the chemical energy stored in diatomic hydrogen (H2). However, there is no accessible natural reserve of uncombined hydrogen, since what little there is resides in Earth's outer atmosphere (exosphere). Hydrogen for use as fuel must first be produced using another energy source; hydrogen would thus actually be a means to transport energy, rather than an energy source, just as common rechargeable batteries are. One existing method of hydrogen production is steam methane reformation; however, the most common source of methane is natural gas, which is in short supply. Another method of hydrogen production is through electrolysis of water which uses electricity generated from any source like renewable energy sources (solar, eolic, etc). If molecular hydrogen could be obtained from the water in an economically viable way it would be a virtually inexhaustible source because its combustion regenerates it back to water.
If we can obtain it from water, hydrogen would be an inexhaustible fuel (Image credit: seujhorg)
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