Aerosols have been an important invention of the 20th century and have revolutionized different industries. A typical aerosol can consist of four parts, the container, actuator, cap and valve. The propellant used for dispensing the contents of the aerosol can were generally CFC based. Now, as there is a global ban on CFC production, the industries have to consider other viable options for the same.
Nowadays, aerosol manufacturers use liquefied gas as a propellant. These could be hydrocarbon gases like propane and butane. These gases have a detrimental effect on the environment as they contribute to the emissions of VOCs (Volatile Organic Compounds). Another alternative which is still in the testing phase is the use of Compressed Gas as a propellant.
Compressed gas technology uses the naturally available gases, Nitrogen or Carbon di Oxide as propellants. They are virtually harmless gases and are found abundantly in our atmosphere, thus they pose no threat to the environment. Flammability is a prime concern for any propellant used in an aerosol. As these gases are naturally occurring, they are non-flammable and the dangers of fire due to mishandling the equipment can be completely eliminated. They also help in eliminating VOCs from the atmosphere. Another added advantage is that they can dispense irrespective of the position of the can.
As this technology is still new as compared to the conventionally used hydrocarbons, there is still research work to be conducted on these propellants. Though they are cheaper than hydrocarbon propellants, they can only be used in certain applications where they do not react with the product present in the can. Water-based and solvent based products react differently with compressed air propellants, so they should be properly selected keeping in mind the nature of the products.