Decolourization of anthraquinone reactive dye by electrochemical reduction on reticulated glassy carbon electrode

• Autor(a) principal: Carneiro,Patricia A.
• Data de Publicação: 2004
• Outros Autores: Boralle,Nivaldo, Stradiotto,Nelson R., Furlan,Maysa, Zanoni,Maria Valnice B.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532004000400023
• topic: reactive dyes; electrochemical reduction; dye treatment; reactive blue 4

The electrochemistry reduction for the removal of Reactive Blue 4 (RB4) dye from aqueous solution using reticulated glassy carbon electrode is investigated. At pH < 8.0 the anthraquinone group of the RB4 dye are reduced in one cathodic step to hidroquinone after a reversible two-electron process involving a precedent two protons reaction. A stable semiquinone is detected by spectrophotometric technique. At pH > 8.0 the reduction process involves two reversible 2-electron steps, whose species are generated by a protonation equilibrium of anthraquinone group. The results shows that 60% of color removal was obtained after 3 hours of RB4 dye electrolysis at acidic and neutral conditions and only 37% at alkaline conditions. Simultaneously 64% of total organic carbon was removed after electrolysis at pH 2.0.