Application of polymeric membranes modified with molecular imprinted polymer nanoparticles for the removal of melamine from aqueous solutions

Melamine (Mel) is a triazine compound that is widely used in industry to produce melamine resin. Melamine template polymer can be syntheyzied according to reported methods in literature and used as selective and intelligent melamine capturing regent and also melamine sensr [1, 2]. In the present work, polyethersulfone (PES)-based mixed matrix membranes (MMMs) with the incorporation of melamine molecularly imprinted polymer (Mel-MIP) as a organic filler was prepared using phase inversion method, and resulting PES/ Mel-MIP nanostructures were characterized by SEM, AFM, and FTIR. It was found that the hydrophilicity of the obtained MMMs was remarkably changed by modification with Mel-MIP nanostructures. Besides, the permeate flux and the anti-fouling properties of all prepared membranes were also studied. The scanning electron microscopy (SEM) images displayed a finger-like and porous structure for all modified membranes. The pure water flux enhanced from 25.3 g/m2 h (the unmodified membrane) to 62.65 g/m2 h (the modified membrane including 0.01 wt.% of Mel-MIP nanoparticles). The membrane antifouling properties were examined by using the egg albumin solution as the model system. The %FFR of the prepared membranes increased from 61.6% for unmodified membrane to 90.3 at highest additive loading, while increasing the Mel-MIP amount from 0.00 to 0.01 wt.% led to a decrease of Rir from 30.3% to 6.69%, respectively. The membrane with 0.005 wt% of Mel-MIP nanoparticles exhibited high efficiency and stability in fluoride removal up to 76%.