An ideal hydrogen-natural gas combination was developed by the Gwangju Institute of Science and Technology (GIST), which is able to capture hydrogen into cage-like molecules that enhance storage efficiency.
Pure hydrogen is held at extremely high pressure (>100 atmospheres) or low temperatures (−20°C), which is naturally a large economic hurdle to the storage of hydrogen, as opposed to hydrocarbons. Gwangju theorized that hydrogen trapping within ice-like crystals would make storage and transport of zero-emission fuel less demanding.
These molecular cages exist in the natural environment and are known as “clathrate hydrates,” which are solid structures based on water, with cavities capable of accommodating different molecules. The use of clathrate hydrates as hydrogen storage containers is being studied by Dr. Youngjune Park, Associate Professor at the Gwangju Institute of Science & Technology in Korea Nevertheless, a very long process is still involved in including pure hydrogen which demands extremely high temperature and pressure.
Instead of trying to generate clathrate hydrates from pure hydrogen, prior researchers proposed that they be mixed with natural gas, which was experimentally proved to promote inclusion under mixed settings. Dr. Park group studied a viable solution to this problem.
The GIST team of scientists has sought to establish the optimal hydrogen-natural gas combination to generate clathrate hydrates energy-efficient. To this goal, clathrate hydrates formed from HNGBs with varied methane, ethane and hydrogen contents have been systematically examined.
Scientists studied the kinetics and structure of the creation and distribution of caught molecules carefully. The team was able specifically to discover the precise gas concentrations at which the hydrogen storage capacity of HNGB hydrates was optimal by acting as a thermodynamic modulator.
The scientists were able to obtain the maximum theoretical hydrogen storage for two types of hydro-clathrate cages, even at moderate pressure and temperature circumstances (<100 atmospheres and (−8°C respectively). The unprecedented findings of the study could thus improve the design of HNGB hydrate storage media. This feat was not reported before.
“Clathrate hydrates and HNGBs could provide a reasonable mid-term solution for storing what is known as ‘blue’ hydrogen, which is hydrogen produced using fossil fuel-based technology but with minimal CO2 emissions.”Dr. Youngjune Park, associate professor from the Gwangju Institute of Science and Technology