Physics

Meteorology

Electrode

Organic chemistry

Chromium

Electrolytic process

Precipitation

Electrolysis

Physical chemistry

Inorganic chemistry

Aqueous solution

Chemistry

Metallurgy

Materials science

Chromium Compounds

Cathode

Titanium

Electrolyte

Hexavalent chromium

Electrochemistry

Journal of Chemical Technology & Biotechnology

The removal of hexavalent chromium from a synthetic solution and from an industrial sample by electrolysis using stainless steel plate and titanium mesh cathodes is studied. It is found that the process proceeds in two steps: (1) electroreduction of hexavalent chromium to trivalent chromium in highly acidic medium and (2) electrochemical precipitation of trivalent chromium in an alkaline medium. A comparative study of electroreduction, electrochemical reduction and chemical reduction of hexavalent chromium is carried out and the electroreduction process is shown to be a clean technique. It is concluded that, in the absence of addition of any chemical as reducing agent, the Cr(III) solution formed on the reduction of Cr(VI) can be recycled in other industrial processes. Copyright © 2003 Society of Chemical Industry

Electrolytic removal of hexavalent chromium from aqueous solutions