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.

Abstract

In this work, CAU-10-H@γ-AlOOH is prepared, and then UTSA-16 is loaded on CAU-10-H@γ-AlOOH to obtain UTSA-16@CAU-10-H@γ-AlOOH. Using the as-prepared composites as stationary materials by cryogenic gas chromatography at 77 K, while CAU-10-H@γ-AlOOH achieves the complete separation of ortho-H2 (o-H2) and D2 with a resolution R of 1.66 and a separation time t of 9.52 min, UTSA-16@CAU-10-H@γ-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 H2/D2 at 77 K, and UTSA-16 can only exert the kinetic sieving effect. UTSA-16's load on CAU-10-H@γ-AlOOH weakens the adsorption of hydrogen isotopes, and the presence of Co2+ in UTSA-16 promotes the conversion of para-H2 to ortho-H2. In gas chromatography, H2 was preferentially desorbed from the system due to strong D2 adsorption caused by the chemical affinity quantum sieving effect and faster H2 diffusion caused by the kinetic sieving effect. These additive effects achieved efficient hydrogen isotope separation at 77 K.