Synthesis, characterization and applications of metallic nanoparticles/rGO blended poly methyl methacrylate membranes for the efficient removal of Cd2+ from model and real wastewater

Abstract

In this study, we report the fabrication of polymer blended thin layer membranes from poly methyl methacrylate (PMMA) as a matrix, and reduced graphene oxide (rGO) and Fe₂O₃, ZnO, CuO and AgO nanoparticles (NPs) as primary and secondary fillers, respectively. The synthesized membranes were characterized by FTIR, XRD, AFM, water contact angle, SEM and EDX analyses. The experimental results revealed that PMMA/rGO/Ag₂O exhibited 99% Cd²⁺ extraction from model aqueous and waste toner carbon solutions at optimized conditions of 6 mM tri-ethanol amine in the membrane phase, 4.21 mM Cd²⁺ concentration in the feed solution and 2.5 M NaOH in the strip solution. This was attributed to the effective particle size of Ag NPs and their ideal chemistry with PMMA and rGO, and the porosity (90%), pore size (0.1–0.72 μm), thickness (0.2 mm) and roughness of PMMA/rGO/Ag₂O, where the latter also resulted in a much higher flux (2.77 × 10⁻² g m⁻² s⁻¹) than many reported membranes. Attributed to high efficiency, cost-effectiveness, and ease of synthesis, the PMMA/rGO/Ag₂O hybrid membrane can be used as an alternative for the remediation of Cd²⁺ from waste toner samples.