(114b) Quantum Molecular Sieving of Isotopic Hydrogen and Methane: Application Potential to Control of Radioactive Elements

Quantum sieving is a new potential technique for separation of isotopes of light mass[1,2]. The quantum sieving is predominant especially for hydrogen isotopes because of their light mass. The quantum molecular sieving was experimentally evidenced with low temperature adsorption and quantum simulation for  single wall carbon nanohorn[3], single wall carbon nanotube (SWCNT)[4,5], activated carbon fiber( ACF)s[4], AlPO₄-5[5], and metal-organic framework[6]. As the quantum molecular sieving effect is predominant at a lower temperature, we need to measure the adsorption characteristics of the nanoporous materials for H₂ and D₂ at low temperature as low as possible.  The boiling temperature of H₂ is 20 K and then adsorption measurement over 20 K is necessary for better understanding of the quantum molecular sieving effect. Also if the quantum molecular sieving effect is evidenced for a heavier molecule such as methane, the application potential of the quantum molecular sieving effect  is highly enhanced.  The quantum molecular sieving effect can be observed mainly in equilibrium adsorption process up to now. No sufficient evidence for kinetic quantum molecular sieving effect using mixed gas is given yet regardless of the theoretical prediction [7] and the importance in application.

  This paper describes quantum molecular sieving effect in equilibrium and kinetic adsorption of H₂/D₂ and CH₄/CD₄on nanoporous carbons together with quantum simulation. The control route for radioactive cabon, ¹⁴C, produced in graphite nuclear reactors with quantum molecular sieving will be proposed.

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