Positively charged nanofiltration (NF) membranes via UV grafting on sulfonated polyphenylenesulfone (sPPSU) for effective removal of textile dyes from wastewater

Pei Shan Zhong, Natalia Widjojo, Tai-Shung Chung*, Martin Weber, Christian Maletzko

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

175 Scopus citations


Novel positively charged nanofiltration (NF) membranes have been fabricated using sulfonated polyphenylenesulfone (sPPSU) support with hydrophilic properties and fully sponge-like morphology via UV-induced grafting. The resultant NF membranes with a mean effective pore diameter of 1.13-1.20nm, molecular weight cut off (MWCO) of 1627-1674Da and high pure water permeability (PWP) of 9-14LMHbar -1 can be successfully developed by utilizing two different types of positively charged grafting monomers. In view of salt rejections of the resultant NF membranes, it follows the order R(MgCl 2)>R(NaCl)>R(MgSO 4)>R(Na 2SO 4) with high rejections to MgCl 2 of up to 95.20%. Furthermore, the newly developed NF1 and NF2 membranes demonstrate an impressive prospect for the dye removal from wastewater treatment. Due to their positive surface charges, a superior rejection of up to 99.98% to Safranin O dye can be achieved by NF1 and NF2 membranes. Characterizations of the two NF membranes were further done to elucidate the difference in performance and a variety of factors such as pore size, surface roughness, selective layer thickness and zeta potential were established as the controlling factors.

Original languageEnglish (US)
Pages (from-to)52-60
Number of pages9
JournalJournal of Membrane Science
StatePublished - Nov 1 2012


  • Dye removal
  • Nanofiltration
  • Positively charged NF membrane
  • UV-initiated grafting

ASJC Scopus subject areas

  • Biochemistry
  • Materials Science(all)
  • Physical and Theoretical Chemistry
  • Filtration and Separation

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