Quantum Effects on the Diffusivity of Hydrogen Isotopes in Zeolites

The molecular sieving of H2 and its isotopes produced by nuclear plants is a long standing research where some adsorption processes are well identified. However, some mechanisms governing the diffusion of the proton and its isotopes within a faujasite NaX at low temperatures (40 -100)K still troublesome to characterize. Notwithstanding, an understanding of the processes governing adsorption diffusion within narrow pores is essential for the development of recycling procedures of gases produced by nuclear plants. At cryogenic temperatures it is well known that quantum effects are revealed and the heterogeneity of the guest structure plays an important role in the adsorption process. Here, we focus on the consequences of these two factors on molecular sieving and transport coefficients, based on molecular dynamics including the Feynman-Hibbs quantum approximation. Our results, show at temperatures below 77K that H2 has a lower adsorption capacity and a lower diffusion coefficient than D2 and T2. Here we giv...