Abstract
A seeded growth procedure was successfully developed to synthesize highly c-oriented and well-intergrown zeolitic imidazolate framework-69 (ZIF-69) membranes on porous α-alumina substrates. The synthesis conditions were optimized both for seed preparation and for secondary growth. For seeding, a facile method was developed to prepare smaller and flat ZIF-69 microcrystals in order to make thin and c-oriented seed layers. While for secondary growth, a synthesis condition that favored the growth along the c-direction was chosen in order to form highly c-oriented ZIF-69 membranes after growth. As a result, the majority of ZIF-69 grains inside the membrane have their straight channels along the crystallographic c-axis aligned perpendicularly to the substrate surface. Such alignment was confirmed by both XRD and pole figure analysis. The mixture-gas separation studies that were carried out at room temperature and 1atm gave separation factors of 6.3, 5.0, 4.6 for CO2/N2, CO2/CO and CO2/CH4 respectively, and a permeance of ∼1.0×10-7molm-2s-1Pa-1 for CO2 in almost all mixtures. Both the separation factor and permeance were better than the performance of the ZIF-69 membranes prepared by the in situ solvothermal method due to improvement in the membrane microstructure by the seeded growth method. © 2011 Elsevier B.V.
Original language | English (US) |
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Pages (from-to) | 46-51 |
Number of pages | 6 |
Journal | Journal of Membrane Science |
Volume | 379 |
Issue number | 1-2 |
DOIs | |
State | Published - Sep 2011 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: We acknowledge the financial support from KAUST distribution fund 31500/4000000066.
ASJC Scopus subject areas
- Biochemistry
- Filtration and Separation
- General Materials Science
- Physical and Theoretical Chemistry