Russian scientists develop fullerene-based hydrogen sorbing agent that meets DOE criteria
Scientists from Saint Petersburg have tested various materials for their ability to absorb hydrogen and found that a composite material consisting of fullerene-containing soot and magnesium hydride meets the targets set out by the U.S. Department of Energy (DOE) for hydrogen transport power systems. Given that hydrogen is likely to be made from biomass in the future, the latest developments in storage technologies are important for the bioenergy community.
The DOE has fixed two targets for hydrogen storage solutions applied to automotive transportation. The first target requires a ratio of hydrogen weight / tank weight that is superior to 0,065 (6,5% weight). This target limits the weight of the tank. The second target requires a hydrogen volumetric density higher than 62 kg/m in order to limit the volume of the tank.
The Russian researchers from the Ceramic Thermal Materials Science and Engineering Centre focused their work on building an experimental hydrogen storage material with a gas weight content of around 60 kilogram and a volume content not less than 5% per cubic meter. Current traditional methods of storing nitrogen, either under high pressure in gaseous condition, or in liquid or adsorbed state, have low hydrogen parameters, both in weight and volume.
To develop their storage method, the scientists looked at various solid sorbents, based on carbon nanostructures - multi-layer nanotubes, astralenes (nanodispersible fulleroid systems) and fullerene-containing soot - which are activery studied around the world. They also analysed specialy treated palladium, magnesium hydride and their composites.
The researchers performed their tests at a special hydrogen test stand able to operate under temperatures from -180 to +800 degrees centigrade and with pressures varying from 0.0001 millimeter mercury column to 20 megapascals, as well as under various environmental conditions.
The scientists found that the inner cavities of all materials (central channels and interlamellar zones of nanotubes and astralenes) do not absorb hydrogen despite any type of specialized preliminary treatment for these materials. Enthusiastic researchers have tested palladium as a catalytic agent, but failed: this metal added only 1-1.5% to hydrogen absorption. Other nanomaterials - graphite fiber, activated carbon, pure fulleren dust, titanium powder and titanium metal hydride - showed much lower sorption values than powders of nanostructural materials.
Fullerene-containing soot appeared to be the winner among sorbent materials:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: biohydrogen :: storage :: materials sciences :: fullerenes :: nanotechnology ::
The researchers prepared a powder of fullerene-containing soot, treated it with glycerol, and added magnesium hydride powder. These manipulations resulted in a sorbing agent the hydrogen sorbing parameters of which fit the requirements for hydrogen storages developed by the U.S. Department of Energy (DOE).
The new sorbent boasts the following parameters: the weight content of hydrogen slightly exceeds 5%, which leads to 65 kg in one cubic meter. Maximum absorption is shown under conditions of 200-350 degrees centigrade and 1-10 megapascals. The reverse process is highly effective at temperatures of 340-350 degrees centigrade.
Image: fullerenes are a family of carbon allotropes - molecules composed entirely of carbon, in the form of a hollow sphere, ellipsoid, or tube.
References:
Russian Information Center: New Horizons of Storing Hydrogen - August 30, 2007.
The DOE has fixed two targets for hydrogen storage solutions applied to automotive transportation. The first target requires a ratio of hydrogen weight / tank weight that is superior to 0,065 (6,5% weight). This target limits the weight of the tank. The second target requires a hydrogen volumetric density higher than 62 kg/m in order to limit the volume of the tank.
The Russian researchers from the Ceramic Thermal Materials Science and Engineering Centre focused their work on building an experimental hydrogen storage material with a gas weight content of around 60 kilogram and a volume content not less than 5% per cubic meter. Current traditional methods of storing nitrogen, either under high pressure in gaseous condition, or in liquid or adsorbed state, have low hydrogen parameters, both in weight and volume.
To develop their storage method, the scientists looked at various solid sorbents, based on carbon nanostructures - multi-layer nanotubes, astralenes (nanodispersible fulleroid systems) and fullerene-containing soot - which are activery studied around the world. They also analysed specialy treated palladium, magnesium hydride and their composites.
The researchers performed their tests at a special hydrogen test stand able to operate under temperatures from -180 to +800 degrees centigrade and with pressures varying from 0.0001 millimeter mercury column to 20 megapascals, as well as under various environmental conditions.
The scientists found that the inner cavities of all materials (central channels and interlamellar zones of nanotubes and astralenes) do not absorb hydrogen despite any type of specialized preliminary treatment for these materials. Enthusiastic researchers have tested palladium as a catalytic agent, but failed: this metal added only 1-1.5% to hydrogen absorption. Other nanomaterials - graphite fiber, activated carbon, pure fulleren dust, titanium powder and titanium metal hydride - showed much lower sorption values than powders of nanostructural materials.
Fullerene-containing soot appeared to be the winner among sorbent materials:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: biohydrogen :: storage :: materials sciences :: fullerenes :: nanotechnology ::
The researchers prepared a powder of fullerene-containing soot, treated it with glycerol, and added magnesium hydride powder. These manipulations resulted in a sorbing agent the hydrogen sorbing parameters of which fit the requirements for hydrogen storages developed by the U.S. Department of Energy (DOE).
The new sorbent boasts the following parameters: the weight content of hydrogen slightly exceeds 5%, which leads to 65 kg in one cubic meter. Maximum absorption is shown under conditions of 200-350 degrees centigrade and 1-10 megapascals. The reverse process is highly effective at temperatures of 340-350 degrees centigrade.
Image: fullerenes are a family of carbon allotropes - molecules composed entirely of carbon, in the form of a hollow sphere, ellipsoid, or tube.
References:
Russian Information Center: New Horizons of Storing Hydrogen - August 30, 2007.
1 Comments:
what does it cost to produce hydrogen ?
moving
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