Wyniki wyszukiwania

1

Photooxidation: a decolorization procedure and a pre-treatment step for biodegradation of reactive azo dye

100%

Genc N., Can-Dogan E.

Polish Journal of Environmental Studies

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2006

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tom 15

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nr 1

In this study, by using a different variety of TiO₂ catalyst, photocatalytic oxidation of reactive azo dye used in textile industry and an improvement in the biodegradability of the dye by photocatalytic oxidation are investigated. It was found that the addition of TiO₂ in the photooxidation of dye increased color removal by 30.84 %, the addition of H₂O₂ in the presence of TiO₂ also increased color removal by 33.98 %. The study also examined the effect of TiO₂ obtained from different companies in color removal and it was found that TiO₂ obtained from Merck and Degussa displayed similar effectiveness in color removal. It was further found that, depending on the chemical composition of dye used, the ions, SO₄²⁻, Cl⁻ and NH₄⁺ emerged and that NH₄⁺ was oxidized to NO₂⁻. As a result of the 42 h long photocatalytic oxidation, a COD removal of about 85.3 % was achieved. In this study, Langmuir-Hinshelwood kinetic constants were examined and it was found that k=0.971 mg/L min and K=0.176 L/mg. By analyzing respirometric measures of raw and photocatalyzed dyes, it was determined that photocatalyzed dye had higher biodegradability than raw dye. Improvement in biodegradation was proven by the rise of BOD₅/COD ratio from 0.06 to 0.29.

2

Discoloration of azo dye Acid Red 18 by Fenton reagent in the presence of iron powder

100%

Barbusinski K., Majewski J.

Polish Journal of Environmental Studies

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2003

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tom 12

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nr 2

The examined H2O2/Fe0 process was found to be very efficient for discoloration of simulated wastewater containing 100 mg/dm3 commercial azo dye Acid Red 18. The optimal doses of H2O2 and Fe0 were 60 and 50 mg/dm3, respectively at pH 3 and 15 minutes reaction time. Under the described conditions total visual discoloration was achieved. A very important factor was reaction time. Generally, the smaller dose of iron powder, the greater reaction time needed for visual discoloration. A strict linear correlation was observed between Fe0 amount in the range of 10–600 mg/dm3 and final pH. This suggests that the H2O2/Fe0 process has undoubted advantages in comparison with the classical Fenton reaction, because using excessive amounts of the iron powder could reach higher final pH in the H2O2/Fe0 process. Thus, smaller doses of base will be required for final neutralization of wastewater. It was also found that the dissolution time of iron powder at acidic conditions (before H2O2 was added) is an important parameter that influences the rate of discoloration. As the time of iron powder dissolution increases, the time needed for visual discoloration decreases.

3

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Textile azo dye decolorization and detoxification using bacteria isolated from textile effluents

86%

Karnwal A.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2019

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tom 100

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nr 4

4

Bis azo dyes - studies on the mechanism of complex formation with IgG modulated by heating or antigen binding

86%

Roterman I., No K. T., Piekarska B., Kaszuba J., Pawlicki R., Rybarska J., Konieczny L.

Journal of Physiology and Pharmacology

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1993

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tom 44

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nr 3

5

Bis-azo dyes interference with efector activation of antibodies

86%

Kaszuba J., Konieczny L., Piekarska B., Roterman I., Rybarska J.

Journal of Physiology and Pharmacology

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1993

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tom 44

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nr 3

6

Advanced oxidative decolorization of Red Cl-5B: effects of dye concentration, process optimization and reaction kinetics

72%

Khan H., Ahmad N., Yasar A., Shahid R.

Polish Journal of Environmental Studies

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2010

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tom 19

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nr 1

83-92

Process conditions (dye concentration, pH and oxidant dose) were optimized for UV, O₃, H₂O₂/UV, O₃/UV, H₂O₂/O₃, and H₂O₂/O₃/UV to treat Red Cl-5B dye of varying concentrations (100, 300, and 500 mg/L). Ozonation resulted in color removal of more than 90%, whereas H₂O₂/O3 showed no advantage over the O₃ alone. However, H₂O₂/UV was found to be very suitable as it gave almost 100% decolorization in a relatively short reaction time. Decolorization rate for all processes was reduced to half when the dye concentration was increased from 100 to 300 mg/l. Comparative study of rate constants revealed that H₂O₂/UV is four times faster than that of UV alone. On the other hand O₃/H₂O₂ is three to four times slower than O₃ alone.

7

Optimum isotherm parameters for reactive azo dye onto pistachio nut shells: comparison of linear and non-linear methods

72%

Armagan B., Toprak F.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 4

Comparison analysis of linear least-square method and non-linear method of three widely used isotherms (Langmuir, Freundlich, and Redlich-Peterson) were examined to experiment with Remazol Red (C.I. 18221) onto pistachio nut shells at a solution temperature of 293 K. All three isotherm equations showed a better fit to the experimental equilibrium data. The results show that the Langmuir model shows the best fit compared to Freundlich and Redlich-Peterson models using the linear method. However, when using the nonlinear method the Freundlich and Langmuir models show the best fit compared to others. Redlich-Peterson isotherm is a special case of Langmuir isotherm when the Redlich-Peterson isotherm constant g was unity.

8

The modified Fenton process for decolorization of dye wastewater

72%

Barbusinski K.

Polish Journal of Environmental Studies

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2005

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tom 14

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nr 3

A novel modified Fenton process using heterogeneous catalyst (swarf) was developed to catalyze the oxidation reaction of azo dye Acid Red 18. It was found that swarf could be used to replace iron salts as a catalyst for the Fenton reaction. The examined continuous Fenton process proved to be very efficient for decolorization of simulated wastewater containing 100 mg/dm³ Acid Red 18. Performance of the Fenton reactor and regeneration method of the catalyst was discussed. The simplified mechanism of hydroxyl radical production in the presence of swarf as a catalyst also was proposed.

9

Wpływ niektórych barwników żywnościowych i kosmetycznych na aktywność oksydazy bursztynianowej

58%

Sikorska E., Krauze S.

Roczniki Państwowego Zakładu Higieny

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1962

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tom 13

|

nr 5

10

Uwagi w związku z koniecznością zmiany polskiego rozporządzenia wykonawczego o barwnikach żywnościowych

51%

Siedlecka J.

Roczniki Państwowego Zakładu Higieny

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1957

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tom 08

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nr 3

Ograniczanie wyników

Photooxidation: a decolorization procedure and a pre-treatment step for biodegradation of reactive azo dye

Discoloration of azo dye Acid Red 18 by Fenton reagent in the presence of iron powder

Textile azo dye decolorization and detoxification using bacteria isolated from textile effluents

Bis azo dyes - studies on the mechanism of complex formation with IgG modulated by heating or antigen binding

Bis-azo dyes interference with efector activation of antibodies

Advanced oxidative decolorization of Red Cl-5B: effects of dye concentration, process optimization and reaction kinetics

Optimum isotherm parameters for reactive azo dye onto pistachio nut shells: comparison of linear and non-linear methods

The modified Fenton process for decolorization of dye wastewater

Wpływ niektórych barwników żywnościowych i kosmetycznych na aktywność oksydazy bursztynianowej

Uwagi w związku z koniecznością zmiany polskiego rozporządzenia wykonawczego o barwnikach żywnościowych