Fabrication of electro spun nylon6.12/chitosan @PES nanofibrous UF membrane towards dyes rejection from synthetic wastewater

Abstract

Nanofibrous ultrafilter of nylon6.12/chitosan@Poly ether sulfone (N6.12/CS@PES) membrane were fabricated by chitosan casted PES membrane and coated with nylon6.12 thin layer using electrospinning technique for dye rejection. The membranes were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The capacity of the membrane to reject both cationic and anionic dyes was evaluated for basic blue dye41 and alizarin red dye, respectively, with regard to solution parameters (pH, Zeta potential, pressure, dye concentration and different electrolyte) through filtration system. In addition, the influence of parameters on dye rejection, as well as their potential interactions, has been investigated. An enhanced hydrophilicity and antifouling property was observed for the composite membrane as compared to pristine PES ultrafiltration membranes. The results show that the rejection of dyes increase with the decreases of operating pressure. At optimum condition of PH = 7, and pressure = 10 bar and concentration = 220 mg/L, the rejection ratio improves from 75.3 to 99.5% and 71 to 82% for basic blue dye41 and alizarin red dye, respectively. Dye rejection is not changed after 7 cycles and not change separation efficiency of dyes. The mechanical and electrical properties were investigated for PES and N6.12/CS@PES composite membrane. The results showed that the N6.12/CS@PES composite membrane exhibited the highest mechanical properties and the highest dielectric constant especially at low frequencies with low dielectric loss. This study demonstrated that the developed nanofibrous composite membrane were successfully characterized and proved to be a good rejection for dyes from aqueous solutions.