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

Abstract

In this study, a new type of polyethersulfone (PES)-based nanofiltration (NF) membrane was fabricated through the modification of membranes surface by using 4-aminobutyric acid-functionalized glycidyl POSS for the improvement of the physicochemical properties and membrane separation performance. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and 3D surface images, pure water flux, water content, water contact angle, salt rejection were used in membrane characterization. The SEM images showed the finger like structure for the modified membranes. Moreover, the SEM images of the membrane surface revealed the excellent dispersion of modified POSS particles on the membrane surface. The water content angle of fabricated membranes declined compared to the virgin PES membrane that indicates the enhancement of membrane hydrophilicity. Water content of the fabricated membranes enhanced from 68% for the neat PES membrane to 77.55% for the one fabricated membrane. However, the pure water flux revealed the decline trend. But among prepared membranes, M3 at 1.5 wt.% COOH-POSS concentration showed the best CrSO 4 rejection (80%) and Na 2 SO 4 rejection (62%). Moreover, M1 at 0.5 wt.% of COO-POSS showed the Pb(NO 3 ) 2 and Cu(NO 3 ) 2 rejection 83% and 80%, respectively