Enhanced oily wastewater treatment: silver nanoparticles-coated graphene oxide/MXene nanocomposite membranes

Abstract

There's growing interest in using membrane technology to treat oily wastewater in industries. Nevertheless, membrane fouling is still a major challenge for removing oil particles from the wastewater. As reducing the membrane fouling requires material and surface science insights, in this work, a nanocomposite membrane was investigated for oily wastewater treatment using synthesized silver nanoparticles (AgNPs) coated graphene oxide (GO)/MXene nanocomposite. The synthesized nanocomposite underwent characterization through FT-IR, XRD, FE-SEM, EDX, and Raman spectroscopy; and in order to characterize the fabricated membranes, SEM, and AFM analysis were applied and the membrane properties such as Hardness, Young’s modulus, thickness, swelling ratio, and Water Contact Angle were studied. The efficiency of the produced membranes was assessed by computing the membrane's oil rejection and permeate flow; the results showed that the rejection was upper than 99.0% and the permeate flux was obtained as high as 160 L/m² h. The study of the membrane surface charge by zeta potential analysis showed that the membrane performance could be optimized in terms of antibacterial and anti-fouling using synthesized nanocomposite membranes; that fully align with the findings of the efficiency of killing the bacteria (E_KB) of different membranes using S. aureus as a Gram-positive and E. coli as a Gram-negative bacterium. The results of membrane fouling analysis showed that the modified membranes with FRR of 96.9% have higher sustainability compared to the PA6 neat membrane (FRR = 65.6%). Moreover, the classic Hermia fouling model revealed that the fouling mechanism of intermediate blocking best explains how fouling affects the membrane's performance.