Modification of polyamide reverse osmosis membranes for the separation of urea
نویسندگان
چکیده
Reverse osmosis (RO) membranes are the gold standard for water desalination and have been in use over three decades. Even though RO exhibit excellent performance rejecting monovalent divalent salt ions, they do not reject small, neutral, uncharged molecules, such as urea, to a level produce potable water, especially at near-neutral pH. Due fast, uncontrolled nature of interfacial polymerization reaction, polyamide layer contains both network aggregate free volume holes (pores). Because urea rejection is dominated by size exclusion mechanism, reducing reduce passage through membrane needed. In this regard, modification increase degree cross-linking and/or decrease hole an ideal approach. We hypothesize that if can be modified with diamine, then will increased. work, we separation layers commercial (Dupont XLE BW30XFR) using carbodiimide chemistry followed application m-phenylenediamine (MPD) heat treatment post-modification stage. The were characterized ATR-FTIR, XPS, SEM, contact angle goniometry, electrokinetic analyzer. Membranes tested permeance, NaCl rejection, dead-end stirred cell. Compared control membranes, BW30XFR improved from 16.8% 54.9% 48.4% 64.6%, but reduction permeance factor up 4.7 2.7 respectively. results show combining MPD enhance significantly.
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ژورنال
عنوان ژورنال: Journal of Membrane Science
سال: 2022
ISSN: ['1873-3123', '0376-7388']
DOI: https://doi.org/10.1016/j.memsci.2022.120584