Nanofiltration membrane based on hyperbranched polyethyleneimine-functionalised multiwalled carbon nanotubes for Pb(II) removal from water

ABSTRACT

Using polysulfone (PSf) as the substrate, a polyamide thin-film composite membrane was synthesised via interfacial polymerisation of hyperbranched polyethyleneimine-functionalised multiwalled carbon nanotubes (HPEI/MWCNTs) and trimesoyl chloride (TMC). The prepared HPEI/MWCNT/PSf nanocomposite membrane was evaluated for the removal of Pb(II). The morphology and physicochemical properties of the prepared membranes were characterised using scanning electron microscopy (SEM), contact angle measurements and flux measurements. The adsorption studies were evaluated using inductively coupled plasma optical emission spectroscopy (ICP-OES). The prepared composite membranes (HPEI/MWCNT/PSf) showed improved Pb(II) removal and enhanced hydrophilicity. The modified membranes were found to be more hydrophilic (contact angle = 63.23°) compared to the neat PSf membrane (contact angle = 122.22°). The water flux for the modified membranes increased linearly with applied pressure. The HPEI/MWCNT/PSf-1% membrane adsorbed more than 95% of Pb(II) ions within 10 minutes.

KEYWORDS:

• Hyperbranched polyethyleneimine (HPEI)
• interfacial polymerisation
• multiwalled carbon-nanotubes
• Pb(II)
• polysulfone

Acknowledgments

We would like to acknowledge the support from the Thuthuka National Research Foundation, South Africa (Grant no: TTK 180427324698), Water Research Commission, South Africa (Project No. K5/2488/3), Eskom TESP: (05.15.286378.15), DST/NPTTP (05.15286415.15), DST/NIC MINTEK, and the Faculty of Science and Centre for Nanomaterials Science Research (CNSR) at the University of Johannesburg, Johannesburg, South Africa.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the Eskom TESP [05.15. 286378.15]; Thuthuka NRF (South Africa) [TTK 180427324698]; Water Research Commission, South Africa [K5/2488/3]; DST/NIC MINTEK [n/a]; Faculty of Science and Centre for Nanomaterials Science Research (CNSR [n/a]; DST/NPTTP [n/a]).