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Title: High-performance ammonia-selective MFI nanosheet membranes
Nanosheet-based MFI membranes, known to be highly selective for hydrocarbon isomer separations, exhibit an NH 3 /N 2 mixture separation factor of 2236 with NH 3 permeance of 1.1 × 10 −6 mol m −2 s −1 Pa −1 , and NH 3 /H 2 separation factor of 307 with NH 3 permeance of 2.3 × 10 −6 mol m −2 s −1 Pa −1 at room temperature. Consistent with a competitive sorption-based separation, lower operating temperatures and higher pressures result in increased separation factor. At 323 K, with an equimolar mixed feed of NH 3 /N 2 , the fluxes and separation factors at 3 and 7 bar are 0.13 mol m −2 s −1 and 191, and 0.26 mol m −2 s −1 and 220, respectively. This performance compares favorably with that of other membranes and suggests that MFI membranes can be used in separation and purification processes involving mixtures of NH 3 /N 2 /H 2 encountered in ammonia synthesis and utilization. The membranes also exhibit high performance for the separation of ethane, n -propane and n -butane from H 2 .  more » « less
Award ID(s):
1705687
PAR ID:
10207972
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Communications
ISSN:
1359-7345
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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