Comparison of three combined sequencing batch reactor followed by enhanced Fenton process for an azo dye degradation: Bio-decolorization kinetics study

Organic synthetic dyes are widely produced and used today. Significant losses of organic and inorganic content occurs during the manufacturing and application of dyes and its discharge in the effluent presents a threat to the eco-systems due to general toxicity and resistance to destruction by biological treatment methods. Particularly azo dyes are of special environmental concern due to their degradation products such as aromatic amines, which are considered highly carcinogenic. So, dyes have to be removed from coloured wastewater before discharge. However, traditional treatment methods (adsorption, coagulation/flocculation) mainly transfer the contaminants from wastewater to secondary waste. Therefore, advanced oxidation processes seem to be sustainable and clean technology to decolorize and minimize organic dyes content from wastewater. In this paper, degradation of an azo dye C.I. Direct Orange 39 (DO39) using Fenton type processes (Fe2+/H2O2, Fe3+/H2O2and Fe0/H2O2) has been performed. The molar ratio of Fentons type reagents has been varied in the range of 1 : 5 up to 1 : 50 at 0.5 and 1.0 mM concentrations of iron salts and iron powder. Experiments have been conducted for two hours in a batch reactor with magnetic stirring, ambient conditions and pH 3. The process efficiency and formation of degradation by-products have been determined on the basis of results obtained by UV/VIS spectrophotometric, total organic carbon (TOC) and high performance liquid chromatography (HPLC) analyses. The optimal Fenton and Fenton ``like" processes parameters have been applied in the photo reactor, too. It has been observed that simultaneous utilization of UV irradiation with Fenton's and Fenton ``like" reagents increases the degradation of DO39 dye. Degradation of the dye in dilute aqueous solution follows pseudo-first order kinetics. The maximal decolourization of 20 mg L-1 DO39 in water of 93.2% and TOC degradation of 76.9% were obtained using Fe3+/H2O2= 1 : 5 molar ratio. The results indicate that the treatment of DO39 dye wastewater with UV/Fe3 +/H2O2 system was found to be the most efficient.

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Decoloration of azo dye methyl orange by a novel electro-Fenton internal circulation batch reactor

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2016-0196 ◽

2017 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Chunwei Yang ◽

Dong Wang ◽

Qian Tang ◽

Yuwei Sun

Keyword(s):

Methyl Orange ◽

Azo Dye ◽

Batch Reactor ◽

Fenton Process ◽

Processing Waste ◽

Internal Circulation ◽

Metal Processing ◽

Graphite Rods

AbstractA novel internal circulation batch reactor (ICBR) was utilized to treat an azo dye pollutant methyl orange (MO) solution by the Electro-Fenton process, with graphite rods as the anodes and metal processing waste iron shavings as the cathodes. The MO decoloration efficiency reached 98.6 % for 0.08 g L

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Performance Analysis of Azo Dye Decolorization by Immobilized Trametes versicolor in a Sequencing Batch Reactor

Environmental Engineering Science ◽

10.1089/ees.2018.0033 ◽

2018 ◽

Vol 35 (12) ◽

pp. 1322-1328

Author(s):

Luis Enrique Lemus-Gómez ◽

Maria Aurora Martínez-Trujillo ◽

Isabel Membrillo-Venegas ◽

Mayola García-Rivero

Keyword(s):

Performance Analysis ◽

Azo Dye ◽

Trametes Versicolor ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Dye Decolorization ◽

Azo Dye Decolorization

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Treatment of dyehouse liquors in a biological sequencing batch reactor with recursive chemical oxidation

Water Science & Technology ◽

10.2166/wst.2001.0257 ◽

2001 ◽

Vol 44 (5) ◽

pp. 85-92 ◽

Cited By ~ 6

Author(s):

R. Krull ◽

D.C. Hempel

Keyword(s):

Partial Oxidation ◽

Azo Dye ◽

Sequencing Batch Reactor ◽

Treatment Cycle ◽

Batch Reactor ◽

Batch Process ◽

Chemical Oxidation ◽

Residual Water ◽

Dye Molecules ◽

Split Flow

A new developed sequencing batch process for the purification of residual water containing concentrated azo dye was investigated. Within a treatment cycle the biological anoxic decolorization, followed by an aerobic mineralization of organic metabolites in combination with the biodegradability-achieving partial oxidation with ozone are carried out sequentially. The split flow can be destructively purified to 90% with respect to the parameter DOC. It was decolorized to an extent of 98% and the toxicity measured by the bioluminescence test decreased up to 99%. With an unspecific facultative anaerobic bacterial mixed culture anoxic decolorization of the residual liquor (20 gdye/L) without addition of an external auxiliary substrate was observed. In the first phase of the treatment cycle, the azo dye-molecules are cleft at the azo bond by biochemical reduction which leads to the corresponding sulfonated aromatic amines. In the following aerobic phase the cleft products were mineralized by the same microorganisms in the same reactor. Because of the recalcitrant and respectively toxic character of a part of the remaining metabolites, further aerobic mineralization was initialized by partial oxidation with ozone. The recursive ozonization in a recircled stream with biological post-treatment of the transformed substances led to an increased reaction selectivity and lower consumption of ozone. The results have shown that the chosen sequencing batch reactor with the ozonization bypass is suitable for an effective treatment of high concentrated dyehouse liquors.

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Combining photo-Fenton process with biological sequencing batch reactor for 2,4-dichlorophenol degradation

Water Science & Technology ◽

10.2166/wst.2004.0288 ◽

2004 ◽

Vol 49 (4) ◽

pp. 293-298 ◽

Cited By ~ 18

Author(s):

F. Al Momani ◽

O. Gonzalez ◽

C. Sans ◽

S. Esplugas

Keyword(s):

Working Conditions ◽

Sequencing Batch Reactor ◽

Irradiation Time ◽

Batch Reactor ◽

Cycle Duration ◽

Biological Oxidation ◽

Fenton Process ◽

Original Solution ◽

Toc Removal ◽

Start Up

The effect of the photo-Fenton process on biodegradability enhancement of 100 mg.L-1 aqueous 2,4-dichlorophenol (2,4-DCP) solution has been investigated. An initial concentration of 65 mg.L-1 H2O2 and 10 mg.L-1 Fe (II) during 35 minutes of irradiation time was sufficient for total 2,4-DCP removal. At these working conditions, biodegradability, measured as BOD5/COD ratio, was increased from 0 for the original solution up to 0.15. Biological oxidation of photo-Fenton pre-treated solutions was performed in a sequencing batch reactor (SBR). After 32 days of start-up, the reactor was fed with different pre-treated solutions and cycle duration was reduced progressively. TOC removal efficiencies in the SBR went from 30 up to 70%.

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Comparison between biological and chemical–physical treatment for colour removal

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0094 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 65-72

Author(s):

G. Farabegoli ◽

L. Pietrelli ◽

E. Rolle ◽

A. Sabene

Keyword(s):

Azo Dye ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Textile Wastewater ◽

Synthetic Wastewater ◽

Physical Treatment ◽

Colour Removal ◽

Biological Reduction ◽

Initial Concentration ◽

Physical Treatments

The main aim of this research is to compare the efficiency of biological and chemical–physical treatments for the removal of organic azo dyes in the textile wastewater. Regarding the biological reduction of the wastewater colour the anaerobic/aerobic (ANA/AER) sequential step-treatment provides the best reductions in colour and COD. A lab-scale Sequencing Batch Reactor (SBR) fed with synthetic wastewater and mono-azo dye (at the initial concentration of 25 mg/l) was used achieving 84% colour reduction and 82% COD removal. Chemical–physical treatments were performed using the oxidative method with Fenton's reagent and adsorption on the activated carbon achieving respectively colour reduction over 90% (from the initial concentration of 250 mg/l) and 155 mg col/g GAC total adsorption capacity (from the initial concentration of 1 g/l).

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Yellow 2G dye degradation by electro-Fenton process using steel electrode as catalysis and its phytotoxicity effect

Water Science & Technology ◽

10.2166/wst.2020.361 ◽

2020 ◽

Author(s):

Amel Benhadji ◽

Mourad Taleb Ahmed

Keyword(s):

Dye Degradation ◽

Batch Reactor ◽

Reaction Times ◽

Fenton Process ◽

Optimum Conditions ◽

Germination Test ◽

Solution Ph ◽

Steel Electrode ◽

Initial Ph ◽

Current Densities

Abstract The heterogeneous electro-Fenton process degradation of Yellow 2G from wastewater was studied using a batch reactor. The COD of the wastewater used in treatment experiments was 163 mg O2·L−1 and the BOD5 was 17 mg O2·L−1 (hardly biodegradable). The treatment of the wastewater at different current densities (2.5 mA·cm−2–12.5 mA·cm−2), solution pH (3 and 6.6), reaction times (5–25 min), electrolyte nature (NaCl, Na2SO4) and electrolyte concentrations (0.15 g·L−1–1 g·L−1) was investigated. According to the results, the heterogeneous electro-Fenton process was suitable for the decolorization of wastewater containing Yellow 2G. The optimum conditions were current density of 12.5 mA·cm−2, initial pH of the wastewater neutral, 25 min of electrolysis treatment using an additive steel electrode as a source of catalysis and in the presence of 1 g NaCl·L−1. We obtained easily biodegradable water with a mineralization rate equal to 85% and non-toxicity confirmed by the pea grain germination test.

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Combined biological and chemical treatment of highly concentrated residual dyehouse liquors

Water Science & Technology ◽

10.2166/wst.1998.0660 ◽

1998 ◽

Vol 38 (4-5) ◽

pp. 339-346 ◽

Cited By ~ 14

Author(s):

R. Krull ◽

M. Hemmi ◽

P. Otto ◽

D. C. Hempel

Keyword(s):

Mixed Culture ◽

Chemical Treatment ◽

Azo Dye ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Reactive Dyes ◽

Water Soluble ◽

Purification Procedure ◽

Biological Degradation ◽

Facultative Anaerobic

The combined biological and chemical treatment of highly concentrated reactive azo dye-containing residual dyehouse liquors with recalcitrant compounds was investigated in a sequencing batch reactor (SBR). The plant consists of a batch reactor in which the anoxic and aerobic phases are carried out by sequenced steps. Water-soluble reactive dyes were reductively cleft and decolorized by a facultative anaerobic bacterial mixed culture under anoxic conditions. Complete decolorization was observed up to concentrations of nearly 20 g dye/L without addition of an external auxiliar substrate. Mineralization of the cleavage products occurs with the same bacterial mixed culture in the same reactor under aerobic conditions. The biomass used for the anoxic treatment is grown in this aerobic phase by the use of split flows with readily biodegradable compounds. Because of the recalcitrant toxic character of some remaining substances, further aerobic mineralization was initiated by partial oxidation with ozone. Partial ozonization in a circulated stream with biological post-treatment of the transformed substances led to an increased reaction selectivity, to a better biological degradation and not least to a lower consumption of ozone. Due to this purification procedure involving highly concentrated residual dyehouse liquors a total decolorization and an overvall degradation of nearly 90% in DOC was achieved.

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