Application of a sequential batch reactor system for textile dyes degradation: comparison between azo and phthalocyanine dyes

• Published in: Water science and technology Vol. 55; no. 10; pp. 107 - 714
• Main Authors: Harrelkas, F, Pons, M.N, Zahraa, O, Yaacoubi, A, Lakhal, E.K
• Format: Journal Article
• Language: English
• Published: England IWA Publishing 01.01.2007
• Subjects: aerobic conditions; Azo Compounds - metabolism; Azo dyes; Bacteria; Bacteria - metabolism; Batch reactors; Biodegradation; Biodegradation, Environmental; Biological treatment; biomass; Bioreactors; Catalysis; cellulose; Chemical industry; chemical oxygen demand; Chemical Physics; cities; Color removal; Coloring Agents - metabolism; Decoloring; Decolorization; Degradation; Dyes; green phthalocyanine dye; Indoles - metabolism; Molecular Structure; particles; photocatalysis; photochemical reactions; Photochemistry - methods; Physics; Pigments, Biological - metabolism; Pretreatment; Reactors; Removal; sequential batch reactor; solar radiation; solutions; textile industry; textile mill effluents; Textiles; Titanium; Titanium dioxide; toxicity; Waste Disposal, Fluid - methods; Wastewater; wastewater treatment; Water Pollutants, Chemical - analysis; inhibition; sequential batch reactor; photocatalysis; Decolouration; supported titanium dioxide
• ISBN: 1843395940; 9781843395942
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2007.313

Photocatalysis on supported TiO2 was combined with aerobic biological treatment in a sequential batch reactor to compare the degradation of two textile dyes: a blue azo dye (DR KBL CDG) and a green phthalocyanine dye (DR K4GN). Three reactors were run in parallel. SBR1 was used as a reference and was fed with urban wastewater only. SBR2 and SBR3 were fed with the same urban wastewater combined with pretreated (for SBR2) and non-pretreated (for SBR3) dye solution. For an azo dye concentration of 12 mg/L decolouration yields of 78 and 27% were achieved, respectively, in SBR2 and SBR3. For the phthalocyanine dye, the decolouration yields decreased to 24 and 15%, respectively. Concerning COD removal it decreases for both dyes with and without pretreatment, when the dye concentration increases. Although a detrimental effect on biomass could be observed, bacteria were able to cope with the inhibitory effect of the dyes.