The maximum absorption capacities of γ-FeOOH, α-FeOOH, γ-Fe2O3 and α-Fe2O3 nanoparticles for As(V) and As(III)

Abstract

γ-FeOOH, α-FeOOH, γ-Fe2O3 and α-Fe2O3 nanoparticle adsorbents for As(V) and As(III) removal were prepared by a chemical coprecipitation method. In the XRD diagrams the oxides appeared in the form of γ-FeOOH, α-FeOOH, γ-Fe2O3 and α-Fe2O3. These typical SEM images of the prepared samples were shown, which reveal that the nanoparticles were about 15 –30 nm. The maximum adsorption capacities of α- FeOOH for As(V) and As(III) were 77.28 and 78.65 mg/g; and γ-FeOOH were 63.75 and 88.99 mg/g respectively and higher than those of γ-Fe2O3 and α-Fe2O3 at pH= 6.0. The adsorption data accorded with Langmuir and Freundlich isotherms. The high adsorption capability and good performance on other aspects make the FeOOH nano particles being a promising adsorbent for the removal of As(V) and As(III) from groundwater.