Innovative modification of bacterial cellulose membrane for high-efficient removal of PFOA substances from water

Global attention has focused on perfluorooctanoic acid (PFOA) because of its environmental persistence, bioaccumulation, and high toxicity. This study investigated evaluating the effectiveness of modified bacterial cellulose membrane (BCM) in removing PFOA from aqueous solutions using the ultrafiltration technique. Epigallocatechin gallate (EGCG) and polyethylenimine (PEI) were cross-linked onto BCM via the Michael addition and Schiff base reaction. The cross-linked layer acted as a functional and adhesive layer to immobilize PEI-grafted carboxylated multi-walled carbon nanotubes (cMP), obtaining BCM/EP/cMP as an adsorptive membrane for PFOA removal. The pure water flux of BCM/EP/cMP was 42.90 ± 2.87 L m -2 h −1 , increased by 40 % compared to BCM. In dynamic filtration, the maximum removal rate of BCM/EP/cMP reached 98.10 % for 5 mg L -1 of PFOA. The incorporation of amine-rich and positively charged cMP enhanced the removal rate of PFOA by 50 % compared to BCM/EP. Additionally, BCM/EP/cMP showed over 83 % removal of natural organic matter (NOM) in antifouling experiments and maintained a flux recovery rate over 88 % after 5 cycles. In summary, the biologically prepared high-efficiency separation membrane showed potential for removing emerging PFOA from aqueous solutions.