New force field for GCMC simulations of D₂/H₂ quantum sieving in pure silica zeolites

Abstract

We report a study on adsorption and coadsorption of H2 and D2 in FAU, MFI and CHA pure silica zeolites having different pore size and shape. Adsorption capacities, selectivities, enthalpies...

High-Throughput Computational Exploration of MOFs with Open Cu Sites for Adsorptive Separation of Hydrogen Isotopes

“…Figure S13a shows the correlation between the D 2 /H 2 selectivity predicted by the fitted FF and the LCD of the MOFs. If taking the distance at the minimum of FH4corrected potential energy curve of H 2 −H 2 (D 2 −D 2 ) interaction as the effective molecular size, 14 the estimated values are 3.58 and 3.46 Å for H 2 and D 2 at 40 K, respectively (Figure S14). To achieve D 2 /H 2 selectivity higher than the benchmark value (13.6) experimentally reported at 40 K for MIL-53(Al), 67 the optimal pore size should be located in the range of 3.8−7.3 Å, which is 1.1−2.1 times that of the effective size of D 2 .…”

“…Therefore, it is of paramount importance to seek more efficient and economical strategies to tackle this obstacle. Since the concept of quantum sieving (QS) was theoretically put forward, it has initiated significant scientific and industrial research actives in the exploitation of diverse nanostructured materials for separating isotopologues, − covering the intensively studied carbonaceous adsorbents − and zeolites. − It has been well recognized that there are two main different mechanisms to govern isotope separation in porous materials, namely the kinetic quantum sieving (KQS) and the one driven by the thermodynamic (TQS) effect . The KQS effect utilizes the principle that lighter isotopes have a higher diffusion barrier than the heavier ones in confined space when the characteristic pore diameter becomes comparable to the de Broglie wavelength (λ) of the lighter molecules.…”

High-Pressure Insertion of Dense H2 into a Model Zeolite

“…Our experimental and theoretical methods are described in the Supporting Information together with the relevant refs. ,− …”

Competition of quantum effects inH2/D2sieving in narrow single-wall carbon nanotubes

“…This size difference becomes critical when the molecules enter nanometric cavities, and can affect both their adsorption and diffusion properties. In the last two decades, the adsorption of H 2 and D 2 has been studied in several nanoporous materials such as carbon nanotubes [14][15][16][17][18][19], zeolites [20][21][22][23], or metal-organic frameworks (MOFs) [24][25][26][27][28][29] with the aim of finding the best candidate for isotopic separation of H 2 and D 2 ; see also Ref 30 and references therein. Very recently, specifically tailored organic cage molecules have been reported to obtain selectivities of up to 8 by combining small pores connecting large cavities [31].…”