“Like Dissolves Like” Strategy Facilitates Interfacial Polymerization for Facile Synthesis of Highly Permeable Reverse Osmosis Membranes
Shenghua Zhou, Wenjia Xu, Zhuting Wang, Keyu Yao, Chaoyuan Ji, Tingzheng Hou, Yan‐Bing He, Hao Guo
Abstract
Existing reverse osmosis (RO) membranes often feature a polyamide rejection layer fabricated by interfacial polymerization (IP) between m -phenylenediamine (MPD) and trimesoyl chloride. However, polyamide RO membrane formation is limited by the poorly soluble polar MPD in the nonpolar organic solvent (e.g., hexane). Herein, we developed a dual organic solvent system to increase MPD solubility via introducing a polar solvent of dioxane into the hexane as inspired by the classical “like dissolves like” theory and thus promoting the IP reaction efficiency. Consequently, the optimal RO membrane exhibited a superior desalination performance with a rejection of 99.2% for 35,000 ppm of NaCl, simultaneous with a high water permeance of 3.1 L m –2 h –1 bar –1 . Meanwhile, it had a boron rejection of 90.3% that far exceeds commercial RO membranes. These findings demonstrate that a dual organic solvent IP system can offer a facile yet effective strategy for scalable fabrication of high-performance RO membranes.