Enhancement of Rhodamine B removal by low-cost fly ash sorption with Fenton pre-oxidation

J Hazard Mater. 2009 Dec 30;172(2-3):1131-6. doi: 10.1016/j.jhazmat.2009.07.106. Epub 2009 Aug 3.

Abstract

The removal of a basic dye, Rhodamine B (RhB), by fly ash adsorption, Fenton oxidation, and combined Fenton oxidation-fly ash adsorption were evaluated. Even though fly ash is a low cost absorbent, a high dose of fly ash was needed to remove RhB. Only 54% of RhB was removed by 80 g L(-1) fly ash. Solution pH did not significantly affect the RhB sorption by fly ash after 8h. Fenton reagents at H(2)O(2) dose of 6 x 10(-3)M and pH 3 rapidly decolorized 97% of RhB within 2 min, and 72% of COD removal was obtained at 30min reaction time. Spectrum analysis result showed that a large area of UV spectrum at 200-400 nm remained after Fenton reaction. The addition of 1gL(-1) fly ash effectively removed COD from Fenton-treated solution, and the UV absorption spectrum at 220-400 nm totally vanished within 2h. COD removal of RhB by the combined Fenton oxidation and fly ash sorption process was 98%. The COD removal capacity of fly ash for Fenton-treated RhB solution was 41.6 times higher than that for untreated RhB solution. The results indicated that the combined process is a potential technique for RhB removal.

Publication types

  • Evaluation Study

MeSH terms

  • Adsorption
  • Carbon / chemistry*
  • Carbon / economics
  • Coal Ash
  • Hydrogen Peroxide / chemistry*
  • Iron / chemistry*
  • Oxidation-Reduction
  • Particulate Matter / chemistry*
  • Particulate Matter / economics
  • Rhodamines / isolation & purification*

Substances

  • Coal Ash
  • Fenton's reagent
  • Particulate Matter
  • Rhodamines
  • Carbon
  • Hydrogen Peroxide
  • Iron
  • rhodamine B