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Title: 2-Methylpyrazine: A Greener Solvent for Nonsolvent Induced Phase Separation (NIPS) Membrane Fabrication
2-Methylpyrazine (2MP), a flavoring agent, was identified and used as a novel greener solvent for nonsolvent-induced phase separation (NIPS) fabrication of poly(ether sulfone) (PES) ultrafiltration (UF) membranes. Flat-sheet membranes were fabricated with 2MP-cosolvent blends, N,N-dimethylacetamide (DMAc), or dimethyl sulfoxide (DMSO), to investigate the influence of solvent choice on membrane properties and performance. The resulting membranes were characterized to assess morphology, productivity, and molecular weight cutoff (MWCO). In addition, kinetic and thermodynamic aspects of solvent choice on the polymer “dope” solutions during the NIPS process were examined. 2MP-cosolvent blends resulted in membranes with noticeably different morphologies, which arise from miscibility-hindered solvent–nonsolvent exchange during membrane formation. Membrane permeance was significantly lower for 2MP-cosolvent membranes when compared to DMAc and DMSO membranes; however, their MWCOs were clearly decreased. This initial study shows that 2MP is a promising greener solvent candidate for NIPS, and further investigations are warranted.  more » « less
Award ID(s):
2029387 1941700
PAR ID:
10516078
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Industrial & Engineering Chemistry Research
Volume:
63
Issue:
24
ISSN:
0888-5885
Page Range / eLocation ID:
10735 to 10747
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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