Simultaneous removal of chromium and leather dye from simulated tannery effluent by photoelectrochemistry

• Published in: Journal of hazardous materials Vol. 166; no. 1; pp. 531 - 537
• Main Authors: Paschoal, Fabiana Maria Monteiro, Anderson, Marc A., Zanoni, Maria Valnice B.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15-07-2009; Elsevier
• Subjects: Applied sciences; Azo Compounds - chemistry; Azo Compounds - radiation effects; Catalysis; Catalytic reactions; Chemical engineering; Chemistry; Chromium - chemistry; Chromium - radiation effects; Chromium reduction; Coloring Agents - chemistry; Coloring Agents - radiation effects; Electrochemical Techniques; Electrodes; Exact sciences and technology; General and physical chemistry; Hydrogen-Ion Concentration; Hydrolyzable Tannins - chemistry; Hydrolyzable Tannins - radiation effects; Industrial Waste - prevention & control; Kinetics; Leather dye; Naphthalenes - chemistry; Naphthalenes - radiation effects; Photobleaching; Photochemical Processes; Photoelectrocatalysis; Photoelectrochemistry; Pollution; Reactors; Surface-Active Agents - chemistry; Surface-Active Agents - radiation effects; Tanning; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; TiO 2 electrode; Titanium; Ultraviolet Rays; Photoelectrochemistry; Photoelectrocatalysis; Chromium reduction; Leather dye; TiO 2 electrode; Discoloration; Pollution control; Sulfates; Electrodes; Electrocatalysis; electrode; Leather industry; pH; Oxidation; Pollution abatement; TiO; Acid dye; Photochemical degradation; Complexation; Pollutant behavior; Photocatalysis; Tannery; Operating conditions; Anionic surfactant; Ultraviolet radiation; Physicochemical purification; Total organic carbon; Kinetics; Titanium oxide; Catalyst
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2008.11.058

The feasibility of the photobleaching of a leather acid dye, acid red 151, simultaneously to degradation of anionic surfactant, Tamol
®, and reduction of Cr(VI) to the less toxic Cr(III) was investigated by photoelectrocatalytic oxidation. The best experimental conditions were found to be pH 2.0 and 0.1
mol
L
−1 sodium sulfate when the nanoporous Ti/TiO
2 photo anode was biased at +1.0
V and submitted to UV-irradiation. The photoelectrocatalytic oxidation promotes 100% discoloration, reducing around 98–100% of Cr(VI) and achieving an abatement of 95% of the original total organic carbon. The effect of pH, the applied potential, the Cr(VI) concentration and the complexation reaction between Cr(VI) and acid red dye were evaluated as to their effect on the kinetics of the reaction.