Abstract
Silicalite-1 membrane was prepared on an outer surface of a tubular α-alumina support by a secondary growth method. Changes of defect amount and crystallinity during secondary growth were carefully observed. The defect-less well-crystallized silicalite-1 membrane was obtained after 7-days crystallization at 373 K. The silicalite-1 membrane became (h0l)-orientation with increasing membrane thickness, possibly because the orientation was attributable to “evolutionally selection”. The (h0l)-oriented silicalite-1 membrane showed high p-xylene separation performance for a xylene isomer mixture (o-/m-/p-xylene = 0.4/0.4/0.4 kPa). The p-xylene permeance through the membrane was 6.52 × 10−8 mol m−2 s−1 Pa−1 with separation factors αp/o, αp/m of more than 100 at 373 K. As a result of microscopic analysis, it was suggested that a very thin part in the vicinity of surface played as effective separation layer and could contribute to high permeation performance.
Original language | English |
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Article number | 949 |
Pages (from-to) | 1-15 |
Number of pages | 15 |
Journal | Crystals |
Volume | 10 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2020 Oct |
Keywords
- Evolutionally selection
- Membrane
- Orientation
- Separation
- Silicalite-1
- Xylene
- Zeolite
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Science(all)
- Condensed Matter Physics
- Inorganic Chemistry