Core-shell graphene oxide-polymer hollow fibers as water filters with enhanced performance and selectivity
Journal article, 2021

Commercial hollow fiber filters for micro- and ultrafiltration are based on size exclusion and do not allow the removal of small molecules such as antibiotics. Here, we demonstrate that a graphene oxide (GO) layer can be firmly immobilized either inside or outside polyethersulfone-polyvinylpyrrolidone hollow fiber (Versatile PES (R), hereafter PES) modules and that the resulting core-shell fibers inherits the microfiltration ability of the pristine PES fibers and the adsorption selectivity of GO. GO nanosheets were deposited on the fiber surface by filtration of a GO suspension through a PES cartridge (cut-off 0.1-0.2 mu m), then fixed by thermal annealing at 80 degrees C, rendering the GO coating stably fixed and unsoluble. The filtration cut-off, retention selectivity and efficiency of the resulting inner and outer modified hollow fibers (HF-GO) were tested by performing filtration on water and bovine plasma spiked with bovine serum albumin (BSA, 66 kDa, approximate to 15 nm size), monodisperse polystyrene nanoparticles (52 nm and 303 nm sizes), with two quinolonic antibiotics (ciprofloxacin and ofloxacin) and rhodamine B (RhB). These tests showed that the microfiltration capability of PES was retained by HF-GO, and in addition the GO coating can capture the molecular contaminants while letting through BSA and smaller polystyrene nanoparticles. Combined XRD, molecular modelling and adsorption experiments show that the separation mechanism does not rely only on physical size exclusion, but involves intercalation of solute molecules between the GO layers.

Author

Alessandro Kovtun

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Antonio Bianchi

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Massimo Zambianchi

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Cristian Bettini

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Franco Corticelli

Institute for Microelectronics and Microsystems

Giampiero Ruani

Consiglio Nazl Ric Inst Nanostruct Mat CNR ISMN

Letizia Bocchi

Medica

Francesco Stante

Stante Laboratories

Massimo Gazzano

Consiglio Nazl Ric Inst Organ Synth & Photoreact

Tainah Dorina Marforio

University of Bologna

Matteo Calvaresi

University of Bologna

Matteo Minelli

University of Bologna

Maria Luisa Navacchia

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Vincenzo Palermo

Chalmers, Industrial and Materials Science, Materials and manufacture

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Manuela Melucci

Institute for organic syntheses and photoreactivity (ISOF-CNR)

Faraday Discussions

1359-6640 (ISSN) 1364-5498 (eISSN)

Vol. 227 274-290

Subject Categories

Polymer Technologies

Materials Chemistry

Other Chemistry Topics

DOI

10.1039/c9fd00117d

PubMed

33300505

More information

Latest update

6/2/2021 9