Since 1970,Rockets commonly use a fuel called Hydrazine to power them through space.Hydrazine was first used as a rocket fuel during world war II and till date,it continued to be the most efficient combustible to propel the rockets.Besides being highly flammable,it produces huge amount of heat and is also used as a low power mono-propellant.
When combined with various catalysts,Hydrazine releases an extremely exothermic reaction that liberates heat in no time,producing energy in the form of large volumes of hot gas from a relatively small volume of hydrazine liquid.
Though it is a very vigorous fuel,it has many significant drawbacks.It is highly toxic when inhaled and when it comes into contact with human skin.Hydrazine equally affects other living beings on earth and thus may cause ecological imbalance.Easily igniting nature of hydrazine makes it very difficult to transport and handle.It also lacks the power that is required to propel future spacecraft systems.
These problems associated with hydrazine made scientists to find a more mild yet powerful fuel.After years of study,the team of researchers from the Air Force Office of Scientific Research have found an alternate fuel for hydrazine that is not only environmentally friendly but also equally efficient and powerful.
NASA has announced that it will stop using hydrazine and switch to this new Eco-friendly propellant.The space agency says that the first rocket that uses this fuel will take place in 2015.
The new propellant is called an energetic ionic liquid or EIL.Usually,Ionic liquids are salt compounds in a liquid form.The molecules in them will possess either positive or negative charge by which they are tightly bonded making the liquid more stable.This liquid is very safe and easy to handle when compared with hydrazine.
It evaporates slowly and its technical name is AF-M315E.However,ionic liquids were considered as less energetic which doesn’t generate high amount of energy when consumed by fire.But the research study states that the ionic liquids can replace very high energy producing fuels like hydrazine.
Its main ingredient is hydroxyl ammonium nitrate.When combusted it releases nontoxic gases such as water vapor,hydrogen and carbon-dioxide thus being environmentally friendly.
Ammonium nitrate which is very explosive is not the same substance as hydroxyl ammonium nitrate.By the addition of hydroxyl group to the molecule,there is a decrease in the melting point of the compound by more than 100 degree Celsius,which makes the gas an ionic liquid.
It proves that the fuel is difficult to ignite and once ignited,the propellant burns hotter than previous propellants.It burns so hot that it could even damage the engines currently in use aboard NASA spacecraft.
“Now we need better materials (for engines) that can handle the temperatures generated,” said Michael Berman, a program manager at the Arlington, Va., Air Force Office of Scientific Research where Hawkins conducts his research.
Ball Aerospace and Technologies Corp.,were allotted the task of designing an engine that can handle EILs.The EIL-based propellants bring safer propulsion systems, along with greater mission flexibility and quick response times.
If the usage of this Eco-friendly fuel proves to be successful,energetic ionic liquids such as M315E could be the fuels for all the future rockets.