Impact of ZnO embedded feed spacer on biofilm development in membrane systems

Avner Ronen, Raphael Semiat, Carlos G. Dosoretz*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

25 Scopus citations

Abstract

The concept of suppressing biofouling formation using an antibacterial feed spacer was investigated in a bench scale-cross flow system mimicking a spiral wound membrane configuration. An antibacterial composite spacer containing zinc oxide-nanoparticles was constructed by modification of a commercial polypropylene feed spacer using sonochemical deposition. The ability of the modified spacers to repress biofilm development on membranes was evaluated in flow-through cells simulating the flow conditions in commercial spiral wound modules. The experiments were performed at laminar flow (Re=300) with a 200kDa molecular weight cut off polysulfone ultrafiltration membrane using Pseudomonas putida S-12 as model biofilm bacteria. The modified spacers reduced permeate flux decrease at least by 50% compared to the unmodified spacers (control). The physical properties of the modified spacer and biofilm development were evaluated using high resolution/energy dispersive spectrometry-scanning electron microscopy, atomic force microscopy and confocal laser scanning microscopy imaging (HRSEM, EDS, AFM and CLSM). HRSEM images depicted significantly less bacteria attached to the membranes exposed to the modified spacer, mainly scattered and in a sporadic monolayer structure. AFM analysis indicated the influence of the modification on the spacer surface including a phase change on the upper surface. Dead-live staining assay by CLSM indicated that most of the bacterial cells attached on the membranes exposed to the modified spacer were dead in contrast to a developed biofilm which was predominant in the control samples.

Original languageEnglish
Pages (from-to)6628-6638
Number of pages11
JournalWater Research
Volume47
Issue number17
DOIs
StatePublished - 1 Nov 2013
Externally publishedYes

Keywords

  • Biofouling
  • Feed spacer
  • Membrane separation
  • Water treatment
  • Zinc oxide nanoparticles

Fingerprint Dive into the research topics of 'Impact of ZnO embedded feed spacer on biofilm development in membrane systems'. Together they form a unique fingerprint.

Cite this