Abstract
MFI type zeolites with 10-membered-ring pores (ca. 0.55 nm) have the ability to separate p-xylene (ca. 0.58 nm) from its bulkier isomers. Here, we introduced non-zeolitic micropores (ca. 0.6–1.5 nm) and mesopores (ca. 2–7 nm) to a conventional microporous MFI type zeolite membrane, yielding an unprecedented hierarchical membrane structure. The uniform, embedded non-zeolitic pores decreased defect formation considerably and facilitated molecular transport, resulting in high p-xylene perm-selectivity and molar flux. Specifically, compared to a conventional, crack network-containing MFI membranes of similar thickness (ca. 1 μm), the mesoporous MFI membranes showed almost double p-xylene permeance (ca. 1.6±0.4×10−7 mol m−2 s−1 Pa−1) and a high p-/o-xylene separation factor (ca. 53.8±7.3 vs. 3.5±0.5 in the conventional MFI membrane) at 225 °C. The embedded non-zeolitic pores allowed for decreasing the separation performance degradation, which was apparently related to coke formation.
| Original language | English |
|---|---|
| Pages (from-to) | 1323-1331 |
| Number of pages | 9 |
| Journal | Angewandte Chemie - International Edition |
| Volume | 60 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2021 Jan 18 |
Bibliographical note
Funding Information:This work was financially supported by the Mid-Career Researcher Program (2020R1A2C1101974), by the Korea CCS R&D Center (KCRC) (2014M1A8A1049309), and by the Super Ultra Low Energy and Emission Vehicle (SULEEV) Center (2016R1A5A1009592) through National Research Foundation (NRF) of Korea. These grants were funded by the Korea government (Ministry of Science and ICT). SK Innovation provided thoughtful insights into the factors related to the p-xylene perm-selectivities of zeolite membranes for real uses in industries. TEM and some SEM characterizations were conducted at KBSI (Seoul Center).
Funding Information:
This work was financially supported by the Mid‐Career Researcher Program (2020R1A2C1101974), by the Korea CCS R&D Center (KCRC) (2014M1A8A1049309), and by the Super Ultra Low Energy and Emission Vehicle (SULEEV) Center (2016R1A5A1009592) through National Research Foundation (NRF) of Korea. These grants were funded by the Korea government (Ministry of Science and ICT). SK Innovation provided thoughtful insights into the factors related to the ‐xylene perm‐selectivities of zeolite membranes for real uses in industries. TEM and some SEM characterizations were conducted at KBSI (Seoul Center). p
Publisher Copyright:
© 2020 Wiley-VCH GmbH
Keywords
- MFI type zeolite membranes
- defect-free membranes
- hierarchical porous structure
- non-zeolitic-pore-containing film
- p-/o-xylene separations
ASJC Scopus subject areas
- Catalysis
- General Chemistry