TY - JOUR
T1 - Quest for an optimal methane hydrates formation in the pores of hydrolytically stable MOFs
AU - Cuadrado-Collados, Carlos
AU - Mouchaham, Georges
AU - Daemen, Luke L.
AU - Cheng, Yongqiang
AU - Ramirez-Cuesta, Anibal J.
AU - Aggarwal, Himanshu
AU - Missyul, Alexander
AU - Eddaoudi, Mohamed
AU - Belmabkhout, Youssef
AU - Silvestre-Albero, Joaquin
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: G.M, M.E and Y.B thank Aramco sponsored research fund (contract. 66600024505). We would like also to acknowledge the support by King Abdullah University of Science and Technology. J.S.A would like to acknowledge financial support from the MINECO (MAT2016-80285-p), Generalitat Valenciana (PROMETEOII/2014/004), Oak Ridge beam time availability (Project IPTS-20859.1) and Spanish ALBA synchrotron (Project 2020014008).
PY - 2020/7/11
Y1 - 2020/7/11
N2 - Porous MOFs capable of storing relatively high amount of dry methane (CH4) in adsorbed phase are largely explored, however solid CH4 storage in confined pores of MOFs in the form of hydrates is yet to be discovered. Here we report a rational approach to form CH4 hydrates by taking advantage of the optimal pore confinement in relatively narrow cavities of hydrolytically stable MOFs. Unprecedentedly, we were able to isolate methane hydrate (MH) nanocrystals with a sI structure encapsulated inside MOF pores with an optimal cavity dimension. It was found, that confined nanocrystals require cavities slightly larger than the unit cell crystal size of MHs (1.2 nm), as exemplified in the experimental case study performed on Cr-soc-MOF-1 vs smaller cavities of Y-shp-MOF-5. Under these conditions, the excess amount of methane stored in the pores of Cr-soc-MOF-1 in the form of MH was found to be 50% larger than the corresponding dry adsorbed amount at 10 MPa. More importantly, the pressure gradient driving the CH4 storage/delivery process could be drastically reduced compared to the conventional CH4 adsorbed phase storage on the dry Cr-soc-MOF-1 (≤3 MPa vs. 10 MPa)
AB - Porous MOFs capable of storing relatively high amount of dry methane (CH4) in adsorbed phase are largely explored, however solid CH4 storage in confined pores of MOFs in the form of hydrates is yet to be discovered. Here we report a rational approach to form CH4 hydrates by taking advantage of the optimal pore confinement in relatively narrow cavities of hydrolytically stable MOFs. Unprecedentedly, we were able to isolate methane hydrate (MH) nanocrystals with a sI structure encapsulated inside MOF pores with an optimal cavity dimension. It was found, that confined nanocrystals require cavities slightly larger than the unit cell crystal size of MHs (1.2 nm), as exemplified in the experimental case study performed on Cr-soc-MOF-1 vs smaller cavities of Y-shp-MOF-5. Under these conditions, the excess amount of methane stored in the pores of Cr-soc-MOF-1 in the form of MH was found to be 50% larger than the corresponding dry adsorbed amount at 10 MPa. More importantly, the pressure gradient driving the CH4 storage/delivery process could be drastically reduced compared to the conventional CH4 adsorbed phase storage on the dry Cr-soc-MOF-1 (≤3 MPa vs. 10 MPa)
UR - http://hdl.handle.net/10754/664293
UR - https://pubs.acs.org/doi/10.1021/jacs.0c01459
U2 - 10.1021/jacs.0c01459
DO - 10.1021/jacs.0c01459
M3 - Article
C2 - 32657126
SN - 0002-7863
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
ER -