Preparation, characterization, characterization, and performance evaluation of sepiolite-based nanocomposite membrane for desalination

A novel polysulfone (poly-AF) and nanocomposite (poly-AF/Sep) membranes thereof were prepared successfully by incorporation of hydrophilic nanorods sepiolite into the polymeric matrix for application in water desalination via reverse osmosis. A novel poly-AF was prepared using a new monomeric pyridine-based diol which itself was synthesized, characterized, and reacted with bis(4-fluorophenyl) sulfone as a dihalide monomer. To improve the hydrophilicity of poly-AF, 1, 3, 5, 7, and 10 wt% sepiolite nanorods were introduced into it by sonication device to achieve a homogeneous solution. Poly-AF and nanocomposite solutions with 30 wt% concentration were used to prepare flat membranes on polyester sheets by non-solvent induced phase inversion through immersion precipitation method. The separation performances of the pristine poly-AF and poly-AF/Sep membranes were studied using evaluation of pure water flux and salt rejection of NaCl. Optimal results of pure water flux of 40.0 Lm(-2 )h(-1) and salt rejection of 99.1% were obtained at 30 bar with cross-flow filtration technique. In addition, the surface of membranes properties was characterized by field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. (C) 2019 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.