Preparation and characterization of a composite nanofiltration membrane interfacially polymerized from cis,cis-1,3,5-triaminocyclohexane and trimesoyl chloride

cis,cis-1,3,5-Triaminocyclohexane (TAC) was synthesized and used to prepare composite nanofiltration (NF) membranes by interfacial polymerization with trimesoyl chloride (TMC). The surface elemental composition, morphology, and hydrophilicity of the prepared NF membranes were characterized. The separation performances were examined with various salts and polyethylene glycol (PEG400, PEG600) solutions. The effects of preparation conditions were also systematically studied. The NF membrane was negatively charged and exhibited a salt rejection in the order Na2SO4 (98.2%)>MgSO4 (90.8%)>MgCl2 (84.5%)>NaCl (54.6%). The water permeability was 1.56L m(-2) h(-1) bar(-1), and the molecular weight cutoff was 600 Da. The TAC/TMC membrane exhibited some characteristics that were different from the ones made from common diamines such as m-phenylenediamine: (1) the surface was smoother, without a ridge-and-valley structure; (2) there were two kinds of crosslinking points in the polyamide chains; (3) the active layer was formed faster (only 5 seconds was required to reach a Na2SO4 rejection of 98%). (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43511.