Mixed Matrix MembranesContaining Green SynthesizedPoly(MBAAm-<i>co</i>-VSPI) Zwitterionic Nanoparticles forthe Removal of Reactive Dyes

Reactive dyes are well known for their color fastness. However, they also display a tendency toward carcinogenicity and mutagenicity. Hence, among the many methods for their removal from dye wastewater, membrane technology appears to be the most viable. In this work, zwitterionic polymeric nanoparticles poly­(MBAAm-<i>co</i>-VSPI) were synthesized via precipitation polymerization following a free radical mechanism using <i>N</i>,<i>N</i>′-methylene bis­(acrylamide) (MBAAm) as a cross-linker and laboratory-synthesized 1-vinyl-3-(3-sulfanatopropyl)-1<i>H</i>-imidazole-3-ium (VSPI) as the monomer. The reaction was carried out in water by utilizing a water-soluble free radical initiator 2,2′-azobis-2-methylpropionamide dichloride (V-50). The resulting nanoparticles were analyzed using FTIR, SEM, EDS, XRD, TGA, zeta potential, DLS, and BET studies. Mixed matrix membranes were fabricated by the incorporation of laboratory-synthesized nanoparticles in the polysulfone (PSf) polymer matrix. Among the series of membranes fabricated, PM-2 showed the highest rejection of the reactive dyes, Reactive Black 5 (RB5 98%) and Reactive Orange 16 (RO16 86%), at 20 ppm concentration along with good pure water permeability of 82.34 L m^–2 h^–1 bar^–1. Hence, this membrane has potential for the treatment of textile wastewater.