H2/D2 Separation Using UTSA-16@CAU-10-H@γ-AlOOH Composites as the Stationary Phase in Gas Chromatography via the Additive Effects of Kinetic Sieving and Chemical Affinity Quantum Sieving

In this work, CAU-10-H@gamma-AlOOH is prepared, and then UTSA-16 is loaded on CAU-10-H@gamma-AlOOH to obtain UTSA-16@CAU-10-H@gamma-AlOOH. Using the as-prepared composites as stationary materials by cryogenic gas chromatography at 77 K, while CAU-10-H@gamma-AlOOH achieves the complete separation of ortho-H-2 (o-H-2) and D-2 with a resolution R of 1.66 and a separation time t of 9.52 min, UTSA-16@CAU-10-H@gamma-AlOOH achieves higher efficiency separation of hydrogen isotopes in a shorter separation time (4.56 min) with R = 1.7. Molecular simulation results show that CAU-10-H has both chemical affinity quantum sieving and kinetic sieving effects for H-2/D-2 at 77 K, and UTSA-16 can only exert the kinetic sieving effect. UTSA-16's load on CAU-10-H@gamma-AlOOH weakens the adsorption of hydrogen isotopes, and the presence of Co2+ in UTSA-16 promotes the conversion of para-H-2 to ortho-H-2. In gas chromatography, H-2 was preferentially desorbed from the system due to strong D-2 adsorption caused by the chemical affinity quantum sieving effect and faster H-2 diffusion caused by the kinetic sieving effect. These additive effects achieved efficient hydrogen isotope separation at 77 K.