Fabrication of layer-by-layer ion exchange membrane by applying PDA-POSS nanocomposite onto heterogeneous cationic substrate for water treatment

Abstract

Double-layer Cation Exchange Membranes (DLCEMs) have been prepared by surface polymerization of dopamine-co-POSS nanoparticles on a PVC-based heterogeneous cation exchange membrane. FTIR and FESEM images proved relatively uniform forming of intended DLCEMs. The FESEM images illustrated almost integrity dispensation of nanoparticles through the surface layer. Results represented that developing a nanocomposite layer resulted in surface hydrophilicity enhancement. The obtained data for Cu 2+ and Cr 2+ removal percentage for the prepared membranes represents a higher capacity for DLCEMs to remove heavy metals compared to the pristine cationic membranes. Also, membranes showed higher Cr 2+ removal capacity rather than Cu 2+ . The membrane surface modification by introducing PDA nanocomposite also caused to improving sodium permeability and flux. Furthermore, the transport number and permselectivity of the prepared CEMs generally follow an increasing procedure nearly. It should be noticed that the incorporation of POSS nanoparticles into the surface layer resulted in electrical resistance reduction obviously.

Co-deposition of COOH-POSS on the surface of PES nanofiltration membranes for improving the permeability and anti-fouling properties

“…This phenomenon can be explained by COOH-POSS accumulation on the membrane surface (see surface images of SEM). Moreover, the obtained results from FRR% and 3D surface images data indicate that the decrease of membrane surface roughness leads to lower fouling [40,41,42,43].…”