Clean Chemical Fuel: Hydrogen

Hydrogen

The Only Truly Clean Chemical Fuel

"In think water will be used one day as a fuel. Hydrogen and Oxygen will be an infinite source for heat and light." Julio Verne, 1870.

Hydrogen (Greek: water former) is an odorless, tasteless, colorless and very reactive element in group 1 of the periodic table. It is the most abundant element of the universe but is hardly found alone;

Hydrogen has two main applications, as fussion and combustion fuel. During rapid oxidation (combustion) Hydrogen is mixed with Oxygen to produce water (H2O) and possible trace amounts of oxides of nitrogen, releasing great amounts of energy in the form of heat. Hydrogen may also be used with Fuel Cells to produce electric power, it's the inverse process to electrolysis.

Hydrogen is gotten from electrolysis by introducing an electric charge to the water through a pair of electrodes, where Hydrogen goes to the catode and Oxygen goes to the anode.

Other ways of getting Hydrogen is heating water at 800F or by chemical reactions between acids (HCl, H₂SO₄) and an active metal (Zn)

Zn(s) + 2H+(ac) --> Zn₂+(ac) + H₂(g)

Advantages:

	It is the only truly clean chemical fuel.
	Hydrogen has a high energetic value, it is more fuel efficient than fossil fuels.
	It produces water during combustion.
	It is not toxic and does not contribute to the Greenhouse Effect, ozone depletion or acid rain.
	It is the most abundant element in nature.
	It can be used as an energy storage (instead of batteries or flywheels for example).
	It produces great heat.
	It is more expenisve to move electrical energy across the continent than an equal amount of hydrogen as a compressed gas by pipeline.
	H₂, When combined with Oxygen, produces 9 times the amount in clean, potable water.

Disadvantages:

	It seldom comes alone.
	It can't be used as a primary energy source.
	More energy is used to produce Hydrogen than what is get from combustion or fuel cells.
	It is very flamable and volatile (metallic alloying storage is a solution to this problem i.e. Fe + Ti. This alloy acts as a sponge and in combination with H2 a fine dust is obtained. Dust heating releases H₂ safely).

Actual technologies are based in combustion fuels, so Hydrogen might be a substitude for a world based on fossil fuels because petroleum prices and pollution are increasing and is a not a renovable fuel. With few changes hydrogen can be used in place of gasoline in an internal-combustion engine.