Chromium contaminated natural water, including surface water and groundwater, are a significant problem as some of the compounds are toxic, mutagenic, and carcinogenic.

José Parga and co-workers, Institute Technology of Saltillo, Mexico, investigated chromium adsorption on iron species for the removal of highly water soluble Cr(VI)/Cr(III) species. They demonstrated that an electrocoagulation process with air injection removes chromium contaminates (> 99 %) without the addition of any chemical reagents. Iron cations produced electrolytically from the iron anodes enhance the coagulation of chromium contaminants from aqueous media through electrostatic attraction between the metals.

• Thermodynamic Studies of Chromium Adsorption on Iron Species Generated by Electrocoagulation
  J. R. Parga, V. Vazquez, G. Gonzalez, M. M. Cisneros,
  Chem. Eng. Technol. 2010, 33 (10).
  DOI: 10.1002/ceat.201000186