Fe 2+ Removal from Water Using PVDF Membranes,Modified with Magnetite Nanoparticles, by Polyelectrolyte Enhanced Ultrafiltration

Abstract

2+ z wody za pomocą membran PVDF modyfikowanych nanocząstkami magnetytu, wspomagane ultrafiltracją z polielektrolitemThe aim of this study was to show results of Fe 2+ removal from water by polyelectrolyte enhanced ultrafiltration on polyvinylidene fluoride membranes modified with magnetite nanoparticles. Magnetite nanoparticles were synthesized by the co-precipitation method and stabilized with sodium polyacrylate. At first stage, the surface of PVDF membranes was modified by grafting of polyethylenimine. At the second stage the polyelectrolyte, grafted to the membrane surface, was used as a linker for magnetite nanoparticles immobilization. The modification of membranes was confirmed by IR spectroscopy, scanning electron microscopy and electro kinetic analysis. The dependence of zeta-potential on pH for PVDF membrane modified with PEI has confirmed the modification of the membrane surface as zeta-potential increases with pH decrease. SEM has shown that the surface of modified membrane is densely covered with nanoparticles, which form clusters. The dependence of the volumetric flux on the applied pressure at various concentrations of the carboxymethylcellulose (CMC) has been studied. Polyelectrolyte enhanced ultrafiltration with CMC has been used for iron(II) removal at initial Fe 2+ concentration of 20 mg/L. The concentrations of iron(II) in permeate using an unmodified membrane has ranged from 0.6 to 1.0 mg/L, whereas for the modified membrane it has been 0.02÷0.08 mg/L.

Biopolymers Applied to Remove Metal Ions Through Ultrafiltration. A Review

“…Konovalova et al [90] studied the elimination of Fe 2+ using CMC through the PEUF method. They compared the effect in PEUF with CMC with a polyvinylidene fluoride (PDVF) membrane modified with nanoparticles of magnetite, which were used as micromixers on the surface of the membrane and another one without modification, both membranes used had a molecular weight of cut 150 kDa.…”