Despite the high potential of zeolite MFI membranes for the separation of important hydrocarbons, their impact on industrial hydrocarbon separations has been limited by challenges in scalable fabrication methods and use of high‐cost membrane supports. Here a one‐step method for fabrication of highly selective and thin (<1 µm) MFI zeolite membranes on low‐cost α‐alumina hollow fiber supports is demonstrated. This is enabled by use of a highly concentrated silicate precursor gel containing MFI nanocrystals that induces a compact membrane layer at the support surface in a single‐step membrane synthesis. These one‐step crystallized MFI hollow fiber membranes show excellent characteristics for butane isomer separation (
Separation of higher hydrocarbons from methane is an important and energy‐intensive operation in natural gas processing. We present a detailed investigation of thin and oriented MFI zeolite membranes fabricated from 2D MFI nanosheets on inexpensive α‐alumina hollow fiber supports, particularly for separation of
- NSF-PAR ID:
- 10455052
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 67
- Issue:
- 1
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract n ‐butane permeance > 10−7mol m−2s−1Pa−1andn ‐butane/i ‐butane separation factors > 50 ), as well as for removal of natural gas liquids (butane, propane, and ethane) from methane at elevated feed pressures up to 9 bar. It is further demonstrated that the scalability of the current strategy by successful fabrication of a high‐quality ten‐membrane module in a single synthesis batch. -
null (Ed.)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
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