Merits of polyoxotungstates as environmental remediation catalysts: a novel wet oxidation technology for refractory industrial pollutants

J Environ Sci Health A Tox Hazard Subst Environ Eng. 2003;38(10):2435-45. doi: 10.1081/ese-120023452.

Abstract

The catalytic effect of silicadodecatungstate (SiW12O40(4-)) on the oxidation of nitrobenzene in subcritical water (T = 100-300 degrees C; P = 0.1-8.6MPa, pH = 2.6) was examined. In the absence of SiW12O40(4-) catalyst nitrobenzene oxidation slowed down significantly after a brief period of rapid degradation and an average of 40% nitrobenzene removal. The catalytic effect of SiW12O40(4-) becomes particularly pronounced after a temperature dependent induction period. Catalyzed wet air oxidation continued until the degradation of the parent compound was complete provided that experimental conditions were harsh enough (T > 200 degrees C). Product distribution analysis suggested that the oxidation paths for catalyzed and uncatalyzed wet air oxidation of nitrobenzene are similar, but the analysis was not definitive.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Industrial Waste
  • Nitrobenzenes / chemistry
  • Nitrobenzenes / isolation & purification*
  • Oxidation-Reduction
  • Polymers
  • Tungsten Compounds / chemistry*
  • Water Purification / methods*

Substances

  • Industrial Waste
  • Nitrobenzenes
  • Polymers
  • Tungsten Compounds
  • nitrobenzene