Arsenic removal using hydrous nanostructure iron(III)-titanium(IV) binary mixed oxide from aqueous solution

J Hazard Mater. 2009 Jan 30;161(2-3):884-92. doi: 10.1016/j.jhazmat.2008.04.034. Epub 2008 Apr 18.

Abstract

The synthetic bimetal iron(III)-titanium(IV) oxide (NHITO) used was characterized as hydrous and nanostructured mixed oxide, respectively, by the Föurier transform infra red (FTIR), X-ray diffraction (XRD) pattern and the transmission electron microscopic (TEM) image analyses. Removal of As(III) and As(V) using the NHITO was studied at pH 7.0 (+/-0.1) with variation of contact time, solute concentration and temperature. The kinetic sorption data, in general, for As(III) described the pseudo-first order while that for As(V) described the pseudo-second order equation. The Langmuir isotherm described the equilibrium data (303 (+/-1.6)K) of fit was well with the Langmuir model. The Langmuir capacity (q(m), mg g(-1)) value of the material is 85.0 (+/-4.0) and 14.0 (+/-0.5), respectively, for the reduced and oxidized species. The sorption reactions on NHITO were found to be endothermic and spontaneous, and took place with increasing entropy. The energy (kJ mol(-1)) of sorption for As(III) and As(V) estimated, respectively, is 9.09 (+/-0.01) and 13.51 (+/-0.04). The sorption percentage reduction of As(V) was significant while that of As(III) was insignificant in presence of phosphate and sulfate. The fixed bed NHITO column (5.1 cm x 1.0 cm) sorption tests gave 3.0, 0.7 and 4.5L treated water (As content < or = 0.01 mg L(-1)) from separate As(III) and As(V) spiked (0.35+/-0.02 mg L(-1)) natural water samples and from high arsenic (0.11+/-0.01 mg L(-1)) ground water, respectively when inflow rate was (0.06 L h(-1)).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Arsenic / toxicity*
  • Hydrogen-Ion Concentration
  • Iron / chemistry*
  • Kinetics
  • Microscopy, Electron, Transmission
  • Nanoparticles / chemistry*
  • Nanotechnology / methods*
  • Oxides / chemistry
  • Phosphates / chemistry
  • Spectroscopy, Fourier Transform Infrared
  • Sulfates / chemistry
  • Titanium / chemistry*
  • Water Pollutants, Chemical / chemistry
  • Water Purification / methods
  • X-Ray Diffraction

Substances

  • Oxides
  • Phosphates
  • Sulfates
  • Water Pollutants, Chemical
  • Titanium
  • Iron
  • Arsenic