Safe immobilization of Cr(III) in heat-treated zeolite tuff compacts

J Hazard Mater. 2006 Sep 21;137(2):1206-10. doi: 10.1016/j.jhazmat.2006.04.004. Epub 2006 Apr 18.

Abstract

The possibility to remove chromium ions from a simulated electroplating wastewater by a discontinuous ion-exchange process based on phillipsite-rich Neapolitan yellow tuff (NYT) has been investigated. The immobilization of the pollutant cation in the resulting sludge through a heat-treatment has been realized, demonstrating that compacts made of Cr-loaded NYT powder, fired at temperatures of 1000 degrees C or over, are safe materials with negligible Cr3+ leaching. The set up overall process allows, in addition, a volume reduction of the waste with associated lower disposal costs or, better, the obtainment of a ceramic material, whose physical and mechanical properties are comparable to those of similar ordinary ceramics, such as bricks. In summary, the proposed strategy looks at the polluted sludge as a resource to be exploited, instead of a dangerous material to safely dispose of.

MeSH terms

  • Cations / pharmacokinetics*
  • Chromium / pharmacokinetics*
  • Zeolites*

Substances

  • Cations
  • Chromium
  • phillipsite
  • Zeolites