Removal of ammonium and heavy metals by cost-effective zeolite synthesized from waste quartz sand and calcium fluoride sludge

Water Sci Technol. 2017 Feb;75(3-4):587-597. doi: 10.2166/wst.2016.508.

Abstract

This study focuses on the effectiveness of zeolite (10% CF-Z [0.5]) hydrothermally synthesized from waste quartz sand and calcium fluoride (CF) for ammonium ion and heavy metal removal. Zeolite was characterized through powder X-ray diffraction, Fourier-transform infrared spectroscopy, micromeritics N2 adsorption/desorption analysis, and field emission scanning electron microscopy. The effects of CF addition, Si/Al ratio, initial ammonium concentration, solution pH, and temperature on the adsorption of ammonium on 10% CF-Z (0.5) were further examined. Results showed that 10% CF-Z (0.5) was a single-phase zeolite A with cubic-shaped crystals and 10% CF-Z (0.5) efficiently adsorbs ammonium and heavy metals. For instance, 91% ammonium (10 mg L-1) and 93% lead (10 mg L-1) are removed. The adsorption isotherm, kinetics, and thermodynamics of ammonium adsorption on 10% CF-Z (0.5) were also theoretically analyzed. The adsorption isotherm of ammonium and lead on 10% CF-Z (0.5) in single systems indicated that Freundlich model provides the best fit for the equilibrium data, whereas pseudo-second-order model best describes the adsorption kinetics. The adsorption degree of ions on 10% CF-Z (0.5) in mixed systems exhibits the following pattern: lead > ammonium > cadmium > chromium.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Ammonium Compounds / analysis*
  • Ammonium Compounds / chemistry
  • Calcium Fluoride / chemistry*
  • Kinetics
  • Metals, Heavy / analysis*
  • Metals, Heavy / chemistry
  • Microscopy, Electron, Scanning
  • Quartz / chemistry*
  • Solutions
  • Spectroscopy, Fourier Transform Infrared
  • Thermodynamics
  • Waste Products
  • Water Pollutants, Chemical / analysis*
  • Water Pollutants, Chemical / chemistry
  • Water Purification / methods*
  • X-Ray Diffraction
  • Zeolites / chemistry*

Substances

  • Ammonium Compounds
  • Metals, Heavy
  • Solutions
  • Waste Products
  • Water Pollutants, Chemical
  • Zeolites
  • Quartz
  • Calcium Fluoride