Ozonation of hydrolyzed azo dye reactive yellow 84 (CI)

Koch, Maximilian; Yediler, Ayfer; Lienert, Doris; İnsel, Güçlü; Kettrup, A.

doi:10.1016/s0045-6535(01)00102-3

Cited by 260 publications

(124 citation statements)

References 6 publications

Supporting

Mentioning

115

Contrasting

Unclassified

Order By: Relevance

“…Typical concentrations of an exhausted RB 5 dye bath are considered to be between 0.8 and 2.6 g l À1 (Arslan and Balcioglu, 2000;Yediler et al, 2000). As the degradation rate of RB5 reacting with ozone depends on the dye concentration and on the ozone consumption, much longer ozonation periods (360 min) were chosen than commonly described (30-60 min) in the related literature (Moraes de Gomes et al, 2000;Ciardelli and Ranieri, 2001;Wu and Wang, 2001;Koch et al, 2002). Results obtained with the laboratory-scale experiments indicate however that a nearly complete decolourization can be achieved after 3 h of ozonation with an ozone concentration of 20.5 mg l À1 .…”

Section: Chemical Oxidationmentioning

confidence: 99%

“…The TOC/ TOC 0 ratio is helpful to assess the mineralization rate but the obtained TOC values may not represent the total TOC concentrations due to the losses of volatile compounds of the aqueous dye solution i.e. formaldehyde, acetaldehyde into the gaseous stream during the ozonation process (Koch et al, 2002).…”

Section: Chemical Oxidationmentioning

confidence: 99%

“…Neither simple chemical nor biological treatment has been proved to be adequate in decolourization and sufficient depletion in organic matter so far (Krull et al, 1998;Koch et al, 2002). Their low BOD 5 /COD ratio values (usually less than 0.1) indicate their resistance to conventional biological treatment (Liakou et al, 1997).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Ozonation of an azo dye C.I. Remazol Black 5 and toxicological assessment of its oxidation products

et al. 2003

View full text Add to dashboard Cite

The effect of ozonation (20.5 mg l À1 ) on the degradation processes of an azo dye, Remazol Black 5 (RB5; CI) was studied. Conventional parameters such as chemical oxygen demand (COD), total organic carbon (TOC), pH, conductivity, colour removal, biodegradability (BOD 5=28 ), and toxic potential of the dye and its degradation products were monitored during the process. The results obtained indicated that ozonation is a highly effective way to remove the colour of a corresponding dye solution. However, a considerable organic load still remained as indicated by high COD and TOC residues. The COD, TOC reductions were about 40% and 25% for 6 h ozonation of 2 g l À1 RB5 aqueous solution. During the ozonation process the rapid decrease of pH and the sharp increase of conductivity indicated the formation of acidic by-products and small fragments and ions which were identified by high performance ion chromatography. The BOD 28 data revealed that first by-products after partial ozonation (10-150 min) of RB5 were more biodegradable than the parent compound and ozonation can enhance the biodegradability of azo dyes. During the first 150 min of total 360 min of oxidation, the formation of first by-products with high toxic potential took place as it could be confirmed by two acute toxicity-screening tests, the bioluminescence test (Vibrio fischerii) and the neutral red cytotoxicity assay (rat hepatoma cells). The significant enhancement of microbial biodegradability after long-term ozonation could also be seen as a decrease of toxic intermediates in correlation with the ozonation time as indicated in BOD 28 biological degradation test results.

show abstract

Section: Chemical Oxidationmentioning

confidence: 99%

Section: Chemical Oxidationmentioning

confidence: 99%

See 1 more Smart Citation

Ozonation of an azo dye C.I. Remazol Black 5 and toxicological assessment of its oxidation products

et al. 2003

View full text Add to dashboard Cite

show abstract

“…The pH of the dye-laden synthetic wastewater was adjusted to pH 7 prior to ozonation using a 0.1 N NaOH solution. The ozonation was evaluated at 5,10,15,20,25,30,35, and 40 min. For a given time, an increase in contact time has resulted in an increase in colour, COD, and TOC removal.…”

Section: Resultsmentioning

confidence: 99%

“…These results may suggest that small organic molecular fragments resulting from the destruction of the dyes are not completely oxidized to CO 2 and wa- ter 12 . The drop in TOC values may suggest that CO 2 molecules are formed simultaneously with other volatile organic compounds such as formaldehyde and acetaldehyde during the ozonation 30 . Ozonation of Bomaplex Red CR-L dye of an initial concentration of 1 g/l approximately results in a 54% COD removal 25 , while ozonation of dyes generally leads to small organic molecular fragments, such as acetic acids, aldehydes, and ketones that result in a residual COD 31 .…”

Section: Resultsmentioning

confidence: 99%

Decolourization of an azo dye in aqueous solution by ozonation in a semi-batch bubble column reactor

Abidin

Fahmi²,

Ong³

et al. 2015

ScienceAsia

View full text Add to dashboard Cite

ABSTRACT:The oxidative degradation of the azo dye Reactive Red 120 by ozonation was investigated. The decolourization was carried out by bubbling ozone at the bottom of a bubble column reactor containing the dye solution. The colour, chemical oxygen demand, and total organic carbon removal were evaluated, and the contaminants were characterized based on the changes in UV-Vis and FT-IR spectra. It was observed that changes of UV-Vis spectra represent the disappearance of both azo and aromatic groups, which causes the colour removal. FT-IR analysis indicated that ozonation shifts the functional groups in the azo dye which results in decolourization, a decrease in aromaticity, and an increase in acidity. The results indicate that the chromophore is destroyed and partially mineralized to small fragments during ozonation. The alkaline pH was favourable to decomposition by ozonation, initiated by the formation of the hydroxyl radicals. The oxidation followed first-order kinetics and the completed decolourization confirmed the capability of ozonation to cleave the azo bond from the dye.

show abstract

Advanced Oxidation Processes, Nanofiltration, and Application of Bubble Column Reactor

Palit

2014

Nanomaterials for Environmental Protection

View full text Add to dashboard Cite

Ozonation of hydrolyzed azo dye reactive yellow 84 (CI)

Cited by 260 publications

References 6 publications

Ozonation of an azo dye C.I. Remazol Black 5 and toxicological assessment of its oxidation products

Ozonation of an azo dye C.I. Remazol Black 5 and toxicological assessment of its oxidation products

Decolourization of an azo dye in aqueous solution by ozonation in a semi-batch bubble column reactor

Advanced Oxidation Processes, Nanofiltration, and Application of Bubble Column Reactor

Contact Info

Product

Resources

About