Antifouling streptomycin-based nanofiltration membrane with high permselectivity for dye/salt separation

Abstract

Nanofiltration (NF) membrane with excellent dye/salt permselectivity and anti-fouling performance is highly desired for the separation of dye/salt mixture in dye wastewater treatment. In this work, the antibacterial NF membrane with high permselectivity and anti-fouling performance was prepared by using a hydrophilic antibiotic, streptomycin (SM) with abundant amino and hydroxyl groups, as the aqueous monomer via interfacial polymerization (IP) with trimesoyl chloride (TMC). The as-prepared antibiotic membrane had a hydrophilic and highly smooth surface, which was beneficial to the membrane anti-fouling performance. The membrane performance was optimized by tuning the concentration of SM, and the optimized membrane with desirable water permeance of 23.5 L·m−2·h−1·bar−1 had excellent dyes rejections (the rejections of Direct red 23 (DR 23), Congo red (CR), Acid red 66 (AR 66), Victoria blue B (VB), and Chrome black T (CBT) were 99.7%, 99.6%, 99.0%, 99.5%, 99.7%, respectively) and low salts rejection (the rejections of NaCl and Na2SO4 were 1.9% and 4.5%, respectively). The optimized membrane also showed excellent separation performance to salt/dye mixed solutions and operational stability. This newly streptomycin-based NF membrane showed excellent application potential in the dye wastewater treatment.