Discoloration and detoxicification of a Congo red dye solution by means of ozone treatment for a possible water reuse.

The objective of this study was to investigate the degradation and mineralization of an azo-dye, the Congo red, in aqueous solutions using ozone. Phytotoxicity and the inhibitory effects on the microbial activity of the raw and the ozonated solutions were also carried out with the aim of water reuse and environment protection. Decolorization of the aqueous solutions, disappearance of the parent compound, chemical oxygen demand (COD) and total organic carbon (TOC) removal were the main parameters monitored in this study. To control the mineralization of the Congo red, pH of the ozonated solution and heteroatoms released from the mother molecule such NH(4)(+), NO(3)(-) and SO(4)(2-) were determined. It was concluded that ozone by itself is strong enough to decolorize these aqueous solutions in the early stage of the oxidation process. Nonetheless, efficient mineralization had not been achieved. Significant drops in COD (54%) were registered. The extent of TOC removal was about 32%. Sulfur heteroatom was totally oxidized to SO(4)(2-) ions while the central -NN- azo ring was partially converted to NH(4)(+) and NO(3)(-). Results of the kinetic studies showed that ozonation of the selected molecule was a pseudo-first-order reaction with respect to dye concentration. The obtained results also demonstrate that ozone process reduced the phytotoxicity of the raw solution and enhanced the biodegradability of the treated azo-dyes-wastewater. Hence, this show that ozone remains one of the effective technologies for the discoloration and the detoxification of organic dyes in wastewater.

[1]  A Yediler,et al.  Ozonation of hydrolyzed azo dye reactive yellow 84 (CI). , 2002, Chemosphere.

[2]  Nader Al-Bastaki,et al.  Removal of methyl orange dye and Na2SO4 salt from synthetic waste water using reverse osmosis , 2004 .

[3]  Xinmiao Liang,et al.  OZONATION OF THE PURIFIED HYDROLYZED AZO DYE REACTIVE RED 120 (CI) , 2002, Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering.

[4]  J. Herrmann,et al.  PHOTOCATALYTIC DEGRADATION OF VARIOUS TYPES OF DYES (ALIZARIN S, CROCEIN ORANGE G, METHYL RED, CONGO RED, METHYLENE BLUE) IN WATER BY UV-IRRADIATED TITANIA , 2002 .

[5]  Ahmet Baban,et al.  Ozonation of high strength segregated effluents from a woollen textile dyeing and finishing plant , 2003 .

[6]  C. Suksaroj,et al.  Treatment of textile plant effluent by nanofiltration and/or reverse osmosis for water reuse , 2005 .

[7]  S. Sandhya,et al.  Decomposition of a dye intermediate, (H-acid) 1 amino-8-naphthol-3,6 disulfonic acid in aqueous solution by ozonation , 2005 .

[8]  Sarina J. Ergas,et al.  Evaluation of Water Reuse Technologies for the Textile Industry , 2006 .

[9]  Johannes Staehelin,et al.  Decomposition of ozone in water: rate of initiation by hydroxide ions and hydrogen peroxide , 1982 .

[10]  J. Herrmann,et al.  Photocatalytic degradation of the alimentary azo dye amaranth: Mineralization of the azo group to nitrogen , 2004 .

[11]  Vera Golob,et al.  Efficiency of the coagulation/flocculation method for the treatment of dyebath effluents , 2005 .

[12]  Huseyin Selcuk,et al.  Decolorization and detoxification of textile wastewater by ozonation and coagulation processes , 2005 .

[13]  C Hessel,et al.  Guidelines and legislation for dye house effluents. , 2007, Journal of environmental management.

[14]  W. Glaze.  Drinking-water treatment with ozone. , 1987, Environmental science & technology.

[15]  H. Shu,et al.  Decolorization effects of six azo dyes by O3, UV/O3 and UV/H2O2 processes , 2005 .

[16]  M. Dezotti,et al.  Ozonation of a landfill leachate: evaluation of toxicity removal and biodegradability improvement. , 2005, Journal of hazardous materials.

[17]  Isil Akmehmet Balcioglu,et al.  Advanced oxidation of a reactive dyebath effluent: comparison of O3, H2O2/UV-C and TiO2/UV-A processes. , 2002, Water research.

[18]  Z. Wang,et al.  Removal of an anionic dye by adsorption/precipitation processes using alkaline white mud. , 2007, Journal of hazardous materials.

[19]  Huixian Shi,et al.  Ozonation of Cationic Red X-GRL in aqueous solution: degradation and mechanism. , 2004, Chemosphere.

[20]  Willy Verstraete,et al.  Treatment and Reuse of Wastewater from the Textile Wet-Processing Industry : Review of Emerging Technologies , 1998 .

[21]  Zijian Wang,et al.  Ozonation of an azo dye C.I. Remazol Black 5 and toxicological assessment of its oxidation products. , 2003, Chemosphere.

[22]  Xinmiao Liang,et al.  Effects of dye additives on the ozonation process and oxidation by-products: a comparative study using hydrolyzed C.I. Reactive Red 120 , 2004 .

[23]  C. Comninellis,et al.  Oxidation of carboxylic acids at boron-doped diamond electrodes for wastewater treatment , 2000 .

[24]  Antonius Kettrup,et al.  Toxicity evaluation of reactive dyestuffs, auxiliaries and selected effluents in textile finishing industry to luminescent bacteria Vibrio fischeri. , 2002, Chemosphere.

[25]  A. L. Marechal,et al.  Comparison of H2O2/UV, H2O2/O3 and H2O2/Fe2+ processes for the decolorisation of vinylsulphone reactive dyes , 2003 .

[26]  F. Kargı,et al.  Color, TOC and AOX removals from pulp mill effluent by advanced oxidation processes: a comparative study. , 2007, Journal of hazardous materials.

[27]  Hans-Peter Bader,et al.  The role of hydroxyl radical reactions in ozonation processes in aqueous solutions , 1976 .

[28]  Shengyu Lin,et al.  Treatment of textile waste effluents by ozonation and chemical coagulation , 1993 .

[29]  B. Keskinler,et al.  Comparison among O3, PAC adsorption, O3/HCO3−, O3/H2O2 and O3/PAC processes for the removal of Bomaplex Red CR-L dye from aqueous solution , 2007 .

[30]  V. Canalli,et al.  Degradation of pararosaniline (C.I. Basic Red 9 monohydrochloride) dye by ozonation and sonolysis , 2006 .

[31]  A. Sadeghi,et al.  Impact of hairy vetch cover crop on herbicide transport under field and laboratory conditions. , 2001, Chemosphere.

[32]  U. Pagga,et al.  The degradation of dyestuffs: Part II Behaviour of dyestuffs in aerobic biodegradation tests , 1986 .

[33]  E. Brillas,et al.  Degradation of herbicide 4-chlorophenoxyacetic acid by advanced electrochemical oxidation methods. , 2002, Environmental science & technology.

[34]  B. Donlon,et al.  Biodegradation of selected azo dyes under methanogenic conditions , 1997 .

[35]  S. Meriç,et al.  Investigation of the relation between COD fractions and the toxicity in a textile finishing industry wastewater: Effect of preozonation , 2007 .

[36]  N. Azbar,et al.  Comparison of various advanced oxidation processes and chemical treatment methods for COD and color removal from a polyester and acetate fiber dyeing effluent. , 2004, Chemosphere.

[37]  Ibrahim M. Banat,et al.  Microbial decolorization of textile-dye-containing effluents A review , 1996 .

[38]  Rip G. Rice,et al.  Applications of ozone for industrial wastewater treatment : A review , 1996 .

[39]  M. Muthukumar,et al.  Decoloration of acid dye effluent with ozone: effect of pH, salt concentration and treatment time , 2005 .

[40]  J Wu,et al.  Ozonation of aqueous azo dye in a semi-batch reactor. , 2001, Water research.

[41]  W. Verstraete,et al.  Treatment and Reuse of Wastewater from the Textile Wet-Processing Industry: Review of Emerging Technologies , 1998 .

[42]  M. Muthukumar,et al.  Studies on the effect of inorganic salts on decolouration of acid dye effluents by ozonation , 2004 .