Hyperbranched polyethyleneimine/multi-walled carbon nanotubes polyethersulfone membrane incorporated with Fe-Cu bimetallic nanoparticles for water treatment

Abstract

Abstract A membrane consisting of highly catalytic Fe-Cu bimetallic nanoparticles, hyperbranched polyethyleneimine (HPEI) and multi-walled carbon nanotubes (MWCNTs) was used in the degradation of 2,4,6-trichlorophenol.A HPEI/MWCNTs/Fe-Cu nanocomposite was fabricated with a polyethersulfone (PES) membrane via the phase-inversion method. The HPEI/MWCNTs/Fe-Cu nanoparticles were immobilised and used as a nanofiller in the preparation of PES ultrafiltration membranes. The fabricated membranes with the different loadings of HPEI/MWCNTs/Fe-Cu/PES were characterised using atomic-force microscopy (AFM), scanning electron microscopy (SEM), and contact angle (CA) measurements. The efficiency of the fabricated membranes to dechlorinate 2,4,6-TCP was investigated using liquid chromatography-mass spectrometry (LC-MS). The SEM micrographs showed finger-like structures for all the prepared membranes. Contact angle measurements revealed the improved hydrophilicity of HPEI/MWCNTs/Fe-Cu/PES compared with bare PES. The antifouling performance of the prepared membranes was evaluated during ultrafiltration using a suspension of bovine serum albumin (BSA) as a model foulantand the flux recovery ratio (FRR) was found to be more than 90%, respectively.The results of the investigation indicated that higher 2,4,6-TCP removal (99.4%) was achieved withthe 0.5 wt% HPEI/MWCNTs/Fe-Cu/PES membrane as well as improved hydrophilicity and improved permeability (26.3 ± 1.3 L/m2.h), compared to those of the 0.1 wt% HPEI/MWCNTs/Fe-Cu/PES membrane.The leachability of Fe and Cu was assessed by using inductively coupled plasma-optical emission spectrometry (ICP-OES). The results showed minimal leaching, thus confirming the strong interaction between nanofillers (HPEI/MWCNTs) and the Fe-Cu bimetallic system.