Functionalized chitosan electrospun nanofiber for effective removal of trace arsenate from water

Sci Rep. 2016 Aug 30:6:32480. doi: 10.1038/srep32480.

Abstract

An environment-friendly iron functionalized chitosan elctrospun nanofiber (ICS-ENF) was synthesized for trace arsenate removal from water. The ICS-ENF was fabricated by electrospinning a mixture of chitosan, PEO and Fe(3+) followed by crosslinking with ammonia vapor. The physicochemical properties of ICS-ENF were characterized by FESEM, TEM-EDX and XRD. The ICS-ENF was found to be highly effective for As(V) adsorption at neutral pH. The As(V) adsorption occurred rapidly and achieved equilibrium within 100 min, which was well fitted by pseudo-second-order kinetics model. The As(V) adsorption decreased with increased ionic strength, suggesting an outer-sphere complexation of As(V) on ICS-ENF. Freundlich model well described the adsorption isotherm, and the maximum adsorption capacity was up to 11.2 mg/g at pH 7.2. Coexisting anions of chloride and sulfate showed negligible influence on As(V) removal, but phosphate and silicate significantly reduced As(V) adsorption by competing for adsorption sites. FTIR and XPS analysis demonstrated -NH, -OH and C-O were responsible for As(V) uptake. ICS-ENF was easily regenerated using 0.003 M NaOH, and the removal rate remained above 98% after ten successively adsorption-desorption recycles. This study extends the potential applicability of electrospun nanofibers for water purification and provides a promising approach for As(V) removal from water.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Arsenates / chemistry
  • Arsenates / toxicity*
  • Chitosan / chemistry
  • Ferric Compounds / chemistry
  • Nanofibers / chemistry*
  • Water / chemistry*
  • Water Pollutants, Chemical / chemistry
  • Water Pollutants, Chemical / toxicity
  • Water Purification*

Substances

  • Arsenates
  • Ferric Compounds
  • Water Pollutants, Chemical
  • Water
  • Chitosan
  • arsenic acid