1.厦门理工学院 环境科学与工程学院;2.厦门理工学院 厦门市膜技术研发与应用重点实验室，福建 厦门361024
Redox mediators can catalyze and accelerate the biodegradation of azo dyes, but they are easily lost in water. The immobilization of the Redox medium on the membrane. provides a new idea for research. In this paper, a redox mediator membrane (AQS-RGO/PVDF) was prepared by phase inversion method using poly(vinylidene fluoride) (PVDF) as the polymer and quinone-based graphene oxide (AQS-RGO) as the Redox medium to explore the catalytic performance of the membrane for the biodegradation of azo dyes. The membranes were characterized by XRD and X-ray photoelectron spectroscopy (XPS), and the results showed that AQS-RGO was successfully immobilized on the membrane. The membrane structure and morphology were characterized by SEM and atomic force microscopy (AFM), and the results showed that the addition of the AQS-RGO mediator made the spongy pores in the membrane denser. Moreover, the contact angle, water flux and rejection of the membrane were measured. It was found that the addition of AQS-RGO made the membrane has better hydrophilicity and permeability, and the maximum pure water flux was 283.09 L/m2?h, which was 4.7 times higher than that of the original PVDF membrane. The AQS-RGO/PVDF membrane prepared under the optimal conditions can shorten the degradation time (decolorization rate ≥90%) of reactive red X-3B from 48h to 30h, indicating that it has a good catalytic effect on the biodegradation of azo dyes. In addition, it can maintain a decolorization rate of more than 90% in 4 cycles of reactive red and acid red dyes. Redox medium membrane has good stability, showing the application potential of the membrane.