Jump to main content
US EPA
United States Environmental Protection Agency
Search
Search
Main menu
Environmental Topics
Laws & Regulations
About EPA
Health & Environmental Research Online (HERO)
Contact Us
Print
Feedback
Export to File
Search:
This record has one attached file:
Add More Files
Attach File(s):
Display Name for File*:
Save
Citation
Tags
HERO ID
7734518
Reference Type
Journal Article
Title
Surface-gel-conversion synthesis of submicron-thick MFI zeolite membranes to expedite shape-selective separation of hexane isomers
Author(s)
Rong, H; Wang, G; Yan, J; Zou, X; Zhu, G
Year
2021
Publisher
Science in China Press
Volume
64
Issue
2
Page Numbers
374-382
Language
English
DOI
10.1007/s40843-020-1400-y
Web of Science Id
WOS:000559948500001
Abstract
Ultrathin zeolite membranes are of paramount importance in accelerating gas transport during membrane separation, and lowering down their membrane thicknesses to submicron scale is deemed to be very challenging. Herein, we develop an advanced approach of surface gel conversion for synthesis of submicron-thick pure silica MFI (silicalite-1) zeolite membranes. Viscous gel is prepared by finely adjusting the precursor composition, enabling its reduced wettability. The unfavorable wetting of the support surface can effectively prevent gel penetration into alumina support voids. Aided by the seeds, the surface gel is directly and fully crystallized into an MFI zeolite membrane with minimal water steam. A membrane with a thickness of 500 nm is successfully acquired and it is free of visible cracks. Additionally, the as-synthesized membranes exhibit rapid and selective separation of hexane isomers by virtue of unprecedentedly high n-hexane permeance of 24.5Ã10â7 mol mâ2 sâ1 Paâ1 and impressive separation factors of 13.3-22.6 for n-hexane over its isomers. This developed approach is of practical interest for sustainable synthesis of high-quality zeolite membranes. © 2020, Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature.
Keywords
zeolite synthesis; silica gel chemistry; thin membrane; hexane separation; isomer selectivity
Home
Learn about HERO
Using HERO
Search HERO
Projects in HERO
Risk Assessment
Transparency & Integrity