Electrochemical decolorization and degradation of Turquoise Blue G (TBG) by pre-adapted petroleum degrading bacteria

• Hybrid technology for degradation of Turquoise Blue G (TBG).
• Electro-oxidation followed by biological route used for degradation of TBG.
• Decolourisation of TBG was observed within 15 min of electrolysis.
• The electrolyzed dye was degraded using pre adapted petroleum degrading Pseudomonas spp.
• Pseudomonas sp. degraded the aromatic to aliphatic compounds.

A combined approach of electrochemical and biological process is applied for the decolorization and degradation of reactive dye Turquoise Blue G (TBG). The complete decolorization of TBG through electrolysis was observed within 15 min using IrO2–RuO2–TiO2–Ti electrode as an anode and Ti as cathode in 5gpl NaCl at pH 7 and a current density of 10 mA/cm2. A new approach for degradation of the electrolyzed dye was carried out using pre-adapted bacterial consortium isolated from petroleum pipelines, which have the ability to grow aerobically in electrochemically decolourized TBG solution. UV–Vis spectra reveal the removal of chromophore and aromatic peaks in electrochemical and biological treatment respectively. The samples were analyzed by high performance liquid chromatography (HPLC). The results suggest that the major dye components were reduced 41.3% by electrochemical and 90% by microbial route and the new peaks generated after biological treatment might be the metabolites of degradation process.