Quantitative analysis of hydrogen isotopes gas mixtures by cryogenic chromatography using low loading MOFs as stationary phase

Exploiting the Specific Isotope-Selective Adsorption of Metal–Organic Framework for Hydrogen Isotope Separation

“…The development of cost-efficient methods of hydrogen isotope separation is essential because of the rapidly increasing demand in medical applications such as imaging and cancer therapy, in scientific applications such as nonradioactive isotope tracing and neutron scattering, and as a fuel for nuclear fusion. − Unfortunately, the existing separation methods, viz., cryogenic distillation and the Girdler sulfide process suffer from low separation efficiencies (typical selectivity of <2.5) due to the nearly identical kinetic diameters and physicochemical properties of protium and deuterium. − ,, Recently, crystalline nanoporous materials such as metal–organic frameworks (MOFs) and zeolites have been proposed as alternatives, supported by two newly proposed quantum sieving (QS) separation mechanisms. The first of these novel mechanisms is kinetic quantum sieving (KQS): D 2 , which has a shorter de Broglie wavelength than H 2 , can diffuse faster through confined pores under cryogenic conditions.…”

“…The first of these novel mechanisms is kinetic quantum sieving (KQS): D 2 , which has a shorter de Broglie wavelength than H 2 , can diffuse faster through confined pores under cryogenic conditions. The second mechanism is chemical affinity quantum sieving (CAQS): D 2 , which has a lower zero-point energy than H 2 , can adsorb preferentially through the strong sorption sites inside crystalline porous materials. − Subsequently, H 2 /D 2 separation techniques utilizing precisely controlled aperture sizes, , local flexibility of apertures, the gating effect of dynamic pore opening, breathing transitions, binding strengths, ,, or two of these properties taken together have led to promising observations. The studies mentioned so far have separated D 2 and H 2 using the minor differences in boiling point, diffusion rate (KQS), and substrate interaction energy (CAQS) rather than utilizing molecular recognition.…”

Efficient hydrogen isotopic analysis with Cu–Fe/ZSM-5 zeolite as a cryogenic chromatographic stationary phase

“…At 5.0 kPa, H 2 , HD, and D 2 peaks were completely resolved, which is consistent with other reports on increased separation resolution by decreasing injection loop pressure. 5 At 95.6 kPa and 5.0 kPa, R (H 2 /HD) = 0.53 and R (HD/D 2 ) = 1.64 and R (H 2 /HD) = 1.34 and R (HD/D 2 ) = 2.23, respectively (Table S3†).…”

“…1,2 Several techniques such as Raman spectroscopy, quadrupolar mass spectrometry, and gas chromatography were developed for this analysis. 3–5 Among them, gas chromatography stands out due to its accuracy of analysis and simplicity of operation and construction. 6,7…”

“…1,2 Several techniques such as Raman spectroscopy, quadrupolar mass spectrometry, and gas chromatography were developed for this analysis. [3][4][5] Among them, gas chromatography stands out due to its accuracy of analysis and simplicity of operation and construction. 6,7 Gas chromatography always relies on column stationary phase materials, which generally include glass microspheres, 8 alumina, 9 metal organic framework composites, 10 and membranes.…”