| Autor: |
Zhang, Xue, Li, Fuzhi, Liu, Mingqiao, Zhu, Chenyu, Zhao, Xuan |
| Předmět: |
|
| Zdroj: |
Journal of Applied Polymer Science; 12/15/2022, Vol. 139 Issue 47, p1-12, 12p |
| Abstrakt: |
The separation efficiency of mono−/divalent cations by a commercial nanofiltration membrane can be enhanced by increasing the surface positive charge. In this study, a novel surface grafting method was suggested, including activation with 2‐chloro‐1‐methyliodopyridine (CMPI), and sequent graft polyethylene‐imine (PEI) and 2,3‐epoxypropyltrimethylammonium chloride (EPTAC). Less flux reduction (<30%) and higher separation factor of Mg2+/Na+ (8.03–9.77) was achieved with the modified membrane under the grafting condition of 0.05 wt% CMPI, 2 wt% PEI, and 1 wt% EPTAC. The modified membranes had higher surface positive charge, hydrophilicity and cross‐linking degree. During the 32‐h filtration of a mixed salt solution, the modified membranes showed larger permeance (>11 L m−2 h−1 bar−1) and higher ion selectivity than the pristine membrane, with separation factors of Mg2+/Na+ and Mg2+/Li+ ranging 36.3–46.2 for the modified membranes. The modified membranes also have higher antifouling properties and are more stable at higher pH condition. The results demonstrate a facile and scalable surface modification method to improve the cation selectivity of commercial NF membranes, which shows great potential in the application of mono−/divalent ion separation. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Plný text