The treatment of liquors containing dissolved chromium

Soluble chromium species (particularly Cr(vi)) are used in many sectors of industry, as shown by the following examples  

L Electroplating of chromium from chromic acid baths leading to spent or contaminated baths and rinsewaters. 

Pickling, etching and stripping solutions in metal finishing. 

Plastic surfaces may be etched, prior to electroplating, by Cr(vi) in order to improve adhesion. 

Chromate conversion coatings (section 8.3.3) for aluminium and magnesium alloys. 

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