Subtle penetrant size effects on separation of carbon molecular sieve membranes derived from $$\mathrm{6FDA:BPDA}$$-$$\mathrm{DAM}$$ polyimide
- Georgia Institute of Technology, Atlanta, GA (United States); OSTI
- Georgia Institute of Technology, Atlanta, GA (United States)
- Dow Chemical Company, Freeport, TX (United States)
Economically scalable carbon molecular sieve (CMS) hollow fiber membranes rely upon a tunable bimodal pore morphology to separate gas pairs using angstrom-level size discrimination. Freshly formed CMS membranes experience self-retarding physical aging, reflected by permeance losses and selectivity gains that stabilize over short times compared to the lifetime of the membrane. Self-retarding morphology rearrangements are of special interest here due to tightening of the largest size range of ultramicropores, thereby causing aging for polyimide-derived CMS. We report effects of such aging for two A/B penetrant pairs, C3H6/C3H8 and CO2/CH4. These two pairs not only have different average sizes, $$\overline{d}_{A/B}$$, but also different size differences,ΔdA/B, between the members in each pair. We focus primarily on the C3H6/C3H8 pair, which is the most difficult of the two pairs to separate, and use some CO2/CH4 results as a comparison case. We study CMS derived from 6FDA:BPDA-DAM (1:1) polyimide by pyrolysis at 550 °C, 600 °C and 650 °C. Here we suggest conditions and physical causes that expedite, retard or even suppress the aging process within CMS membranes. Finally, we suggest how analysis of CMS derived from other precursors and other penetrant pairs can be generalized by understanding the results for the 6FDA:BPDA-DAM (1:1) polyimide derived CMS.
- Research Organization:
- Georgia Institute of Technology, Atlanta, GA (United States)
- Sponsoring Organization:
- Dow Chemical Company; USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- FG02-04ER15510
- OSTI ID:
- 1976905
- Alternate ID(s):
- OSTI ID: 1813884
- Journal Information:
- Carbon, Journal Name: Carbon Journal Issue: C Vol. 184; ISSN 0008-6223
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Hyperaging Tuning of a Carbon Molecular-Sieve Hollow Fiber Membrane with Extraordinary Gas-Separation Performance and Stability
Hyperaging Tuning of a Carbon Molecular‐Sieve Hollow Fiber Membrane with Extraordinary Gas‐Separation Performance and Stability
Journal Article
·
Mon Jun 10 20:00:00 EDT 2019
· Angewandte Chemie (International Edition)
·
OSTI ID:1594570
Hyperaging Tuning of a Carbon Molecular‐Sieve Hollow Fiber Membrane with Extraordinary Gas‐Separation Performance and Stability
Journal Article
·
Wed Jul 10 20:00:00 EDT 2019
· Angewandte Chemie
·
OSTI ID:1542473