Composites of polypyrrole and carbon black: 4. Use in environmental pollution abatement of hexavalent chromium Original Research Article

Composites of an electronically conducting polymer (polypyrrole) with carbon black were used to reduce Cr(VI) to (the less toxic) Cr(III) in aqueous media. The carbon black content in these composites was varied from ~5 to ~65% (by weight); an increase in the carbon black fraction increased the ability of the composite to reduce Cr(VI). The composite outperformed both its components, namely polypyrrole and carbon black, in its ability to treat Cr(VI). The Cr(VI) conversion obeyed pseudo firstorder kinetics. The mechanistic and practical implications of this new Cr(VI) pollution abatement approach are discussed.