How can hexavalent chromium be removed from aqueous waste streams?

How can hexavalent chromium be removed from aqueous waste streams?
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1 Answer

Answer :

One option is to use ferrous sulfate to reduce the hexavalent chromium to a less toxic, trivalent  chromium form that wills precipitate out of the solution. Trivalent chromium can then be reduced by  sodium hydroxide.
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