Low-field NMR relaxation-exchange measurements for the study of gas admission in microporous solids

Understanding the uptake and storage of gases by microporous materials is important for our future energy security. As such, we demonstrate here the application of two-dimensional NMR relaxation experiments for probing the admission and corresponding exchange dynamics of methane within microporous z...

Full description

Saved in:
Bibliographic Details
Published in:Physical chemistry chemical physics : PCCP 2020-06, Vol.22 (24), p.13689-13697
Main Authors: Robinson, Neil, Xiao, Gongkui, Connolly, Paul R. J, Ling, Nicholas N. A, Fridjonsson, Einar O, May, Eric F, Johns, Michael L
Format: Article
Language:English
Subjects:
Ambient temperature
Correlation analysis
Data acquisition
Diffusion length
Diffusion rate
Energy storage
Gases
Methane
NMR
Nuclear magnetic resonance
Zeolites
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Understanding the uptake and storage of gases by microporous materials is important for our future energy security. As such, we demonstrate here the application of two-dimensional NMR relaxation experiments for probing the admission and corresponding exchange dynamics of methane within microporous zeolites. Specifically, we report low-field (12.7 MHz) 1 H NMR relaxation-exchange correlation measurements of methane within commercial LTA zeolites (3A and 4A) at 25 and 35 bar and ambient temperature. Our results demonstrate the clear identification of bulk-pore and pore-pore exchange processes within zeolite 4A, facilitating the calculation and comparison of effective exchange rate dynamics across varying diffusion length scales and gas pressures. Additional data acquired for zeolite 3A reveals the sensitivity of NMR relaxation phenomena to size-exclusive gas admission phenomena, illustrating the potential of benchtop NMR protocols for material screening applications. We demonstrate how low-field NMR relaxation-exchange correlation measurements permit the non-invasive characterisation of methane exchange dynamics within microporous LTA zeolites.
ISSN:1463-9076
1463-9084
DOI:10.1039/d0cp02002h