Cryo-adsorption
Encyclopedia
Cryo-adsorption is a method used for hydrogen storage
where gaseous hydrogen
at cryogenic temperatures (150 - 60 K) is physically adsorbed on porous material, mostly activated carbon
. The achievable storage density
is between liquid hydrogen
(LH2) storage systems and compressed hydrogen
(CGH2) storage systems.
Hydrogen storage
Hydrogen storage describes the methods for storing H2 for subsequent use. The methods span many approaches, including high pressures, cryogenics, and chemical compounds that reversibly release H2 upon heating...
where gaseous hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
at cryogenic temperatures (150 - 60 K) is physically adsorbed on porous material, mostly activated carbon
Activated carbon
Activated carbon, also called activated charcoal, activated coal or carbo activatus, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions.The word activated in the name is sometimes replaced...
. The achievable storage density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...
is between liquid hydrogen
Liquid hydrogen
Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...
(LH2) storage systems and compressed hydrogen
Compressed hydrogen
Compressed hydrogen is the gaseous state of the element hydrogen kept under pressure. Compressed hydrogen in hydrogen tanks at 350 bar and 700 bar is used for mobile hydrogen storage in hydrogen vehicles...
(CGH2) storage systems.