Preparation, Characterization, and Performance of Sulfated Chitosan/Polyacrylonitrile Composite Nanofiltration Membranes

Abstract

Sulfated chitosan composite nanofiltration (NF) membranes having polyacrylonitrile (PAN) ultrafiltration (UF) membrane as the base material are prepared by coating and cross-linking, in which epichlorohydrin (ECH) aqueous solution is used as the cross-linking agent. Newly prepared membranes are characterized by FTIR-ATR, XRD, NMR, TGA, and SEM. Effects of various factors like concentration of cross-linking agent, casting solutions, and membrane preparation conditions on the performance of newly prepared composite NF membranes are studied. The results showed that the NF membrane with excellent rejection performance has 1.0 wt% of sulfated chitosan concentration, 0.4 wt% ECH concentrations, 1 hour cross-linking at 60°C. With this composite NF membrane, the solutes rejection from electrolyte solutions is observed to be in the order: R _ZnSO4 > R _CuSO4 > R _ZnCl2 > R _CuCl2. Due to adsorption of anions from electrolyte solution, the active layer of the membrane develops a negative surface charge.

Keywords:

• Composite membrane
• permeation
• polyacrylonitrile
• rejection
• sulfated chitosan

Acknowledgments

L. B. Chaudhari acknowledges the financial support from the Management of Sardar Vallabhbhai Patel Education Society, Isroli–Bardoli, Surat, for obtaining the Perma-pilot scale membrane system.