Fe-based ceramic nanocomposite membranes fabricated via e-spinning and vacuum filtration for Cd 2+ ions removal

Chemosphere. 2019 Sep;230:527-535. doi: 10.1016/j.chemosphere.2019.05.084. Epub 2019 May 16.

Abstract

In this work, vacuum filtered and polymer mixed e-spinning membranes (ESPMs) made from or doped with Fe-based nanomaterials were successfully fabricated to remove Cd2+ ions from a neutral aqueous solution. The used Fe-based nanomaterials including FeOOH precursor Nanowires (NWs), α-Fe2O3 NWs and Fe3O4 nanoparticles (NPs) were synthesized by elevating the hydrothermal reaction temperature from 250 °C to 500 °C or doing post-heating treatment. The adsorption results showed that vacuum filtered membranes (VFMs) overall performed a better Cd2+ ions removal behavior than e-spinning ones. Among them, VFM made from Fe3O4 NPs has the highest adsorption capacity (qt) with the adsorption amount of Cd2+ ions reaching about 29.3 mg/g within only 2 min due to the high specific surface area of NPs. Models of pseudo-first-order, pseudo-second-order and intraparticle diffusion were used to study the kinetics of Cd2+ ions removal process, and a high correlation coefficient (R2) of 0.99 was obtained when pseudo-second-order model was used. It was calculated that the equilibrium rate constant of VFM made from Fe3O4 NPs has reached about 0.28 g mg-1 min-1, much smaller than those of other membranes, which indicated a high Cd2+ ions removal efficiency.

Keywords: Adsorption kinetics; Cd(2+) ions removal; Fe-based ceramic nanomaterials; Membrane.

MeSH terms

  • Adsorption
  • Cadmium / analysis*
  • Ceramics / chemistry*
  • Diffusion
  • Ferrosoferric Oxide / chemistry*
  • Filtration / methods*
  • Membranes, Artificial
  • Models, Theoretical
  • Nanocomposites / chemistry*
  • Vacuum
  • Water Pollutants, Chemical / analysis*
  • Water Purification / methods*

Substances

  • Membranes, Artificial
  • Water Pollutants, Chemical
  • Cadmium
  • Ferrosoferric Oxide