Development of asymmetric BTDA-TDI/MDI (P84) copolyimide flat sheet and hollow fiber membranes for ultrafiltration: Morphology transition and membrane performance
Ren, J; Li, Z
| HERO ID | 3577379 |
|---|---|
| In Press | No |
| Year | 2012 |
| Title | Development of asymmetric BTDA-TDI/MDI (P84) copolyimide flat sheet and hollow fiber membranes for ultrafiltration: Morphology transition and membrane performance |
| Authors | Ren, J; Li, Z |
| Journal | Desalination |
| Volume | 285 |
| Page Numbers | 336-344 |
| Abstract | In this paper, the effects of gamma-butyrolactone (GBL) weight ratio (w(GBL)) and membrane thickness on the formation of asymmetric flat sheet membranes prepared with P84 (BTDA-TDI/MDI co-polyimide)/N-methyl-2-pyrrolidone (NMP)/GBL casting solutions are investigated. With the increase of membrane thickness, the transition of membrane morphology from sponge-like to finger-like structure occurs at critical structure-transition thickness L-c. L-c and the general sponge-like structure thickness (L-gs) increase with w(GBL). For 20 wt.% P84/NMP/GBL casting solution, the membrane morphology changes from finger-like to sponge-like structure at the critical weight ratio of GBL (w* = 0.69). The membrane morphology and performance of hollow fibers spun with various w(GBL) are observed. Compared with the hollow fiber membranes made of 18 wt.% P84/NMP/GBL dope solution with w(GBL) = 0.75, the hollow fiber membranes spun with w(GBL) = 0.25 present a higher permeation flux and a larger MWCO. As w(GBL) increases from 0.25 to 0.75, the membrane morphology transfers from finger-like to sponge-like structure. An increase in shear rate shifts the rejection curves towards left, and lowers the MWCO of hollow fiber membranes. For hollow fiber membranes spun with w(GBL) = 0.75, a relatively high permeation flux and a large MWCO are obtained by the wet spinning process. (C) 2011 Elsevier BM. All rights reserved. |
| Doi | 10.1016/j.desal.2011.10.024 |
| Wosid | WOS:000300478100044 |
| Is Certified Translation | No |
| Dupe Override | No |
| Comments | Journal: ISSN: |
| Is Public | Yes |
| Keyword | Membrane morphology; Membrane thickness; Hollow fiber membrane; Ultrafiltration; Pore size distribution |