Tailoring interfacially polymerized thin-film composite polyesteramide nanofiltration membranes based on carboxylated chitosan and trimesoyl chloride for salt separation

Thin-film composite polyesteramide nanofiltration membrane prepared from carboxylated chitosan and trimesoyl chloride was carefully tailored during its fabrication process of interfacial polymerization. The effects of post-curing, mid-drying and the addition of phase transfer catalysts on the membrane properties were studied using single-factor experiment. Post-curing was found to be effective in improving the separation performance of the membrane containing high concentrations of carboxylated chitosan, and the optimal post-curing effect was achieved at a temperature of 40 degrees C and curing time range of 15-20 min. Mid-drying enhanced the permeation flux and salt rejection of the membrane containing low concentrations of carboxylated chitosan, and the optimum temperature range for the mid-drying process was obtained at 30-40 degrees C. Furthermore, the membrane properties were susceptible to the addition of phase transfer catalysts, and a uniformly distributed phase transfer catalyst is vital to its influence on membrane properties. The addition of 0.025 wt% benzyl-triethylammonium chloride to the aqueous solution exhibited the best effect towards the improvement of the separation performance of the produced membrane. (C)2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.