scholarly journals Azo Dye Degradation by Chlorella vulgaris: Optimization and Kinetics

2019 ◽  
Vol 14 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Totiya Ishchi ◽  
G. Sibi
Keyword(s):  
Chlorella Vulgaris ◽  
Azo Dye ◽  
Dye Degradation

Degradation of an Azo Dye by Fenton Type Processes Assisted with UV Irradiation

2007 ◽  
Vol 5 (1) ◽  
Author(s):  
Natalija Koprivanac ◽  
Dinko Vujevic
Keyword(s):  
Uv Irradiation ◽  
Azo Dye ◽  
Dye Degradation ◽  
Degradation Products ◽  
Batch Reactor ◽  
Process Efficiency ◽  
Molar Ratio ◽  
Synthetic Dyes ◽  
Ambient Conditions ◽  
Treatment Methods

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 Fenton’s 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.

scholarly journals Azo dye degradation by Phanerochaete chrysosporium in the medium enriched with nitrogen in the presence of primary co-substrate

2013 ◽  
Vol 56 (5) ◽  
pp. 867-874 ◽  
Author(s):  
Marcus Vinicius Freire Andrade ◽  
Karla Mayara Lima da Silva ◽  
João Paulo da Silva Siqueira ◽  
Carlos Ronald Pessoa Wanderley ◽  
Rinaldo dos Santos Araújo ◽  
...  
Keyword(s):  
Phanerochaete Chrysosporium ◽  
Azo Dye ◽  
Dye Degradation

Fe-based metallic glass catalyst with nanoporous surface for azo dye degradation

Chemosphere ◽  
2017 ◽  
Vol 174 ◽  
pp. 76-81 ◽  
Author(s):  
Z. Deng ◽  
X.H. Zhang ◽  
K.C. Chan ◽  
L. Liu ◽  
T. Li
Keyword(s):  
Metallic Glass ◽  
Azo Dye ◽  
Dye Degradation ◽  
Nanoporous Surface

Role of Enzymes From Microbes in the Treatment of Recalcitrant From Industries

2018 ◽  
pp. 395-420
Author(s):  
Veena Gayathri Krishnaswamy
Keyword(s):  
Fresh Water ◽  
Azo Dyes ◽  
Azo Dye ◽  
Dye Degradation ◽  
Anthropogenic Activities ◽  
Bacterial Degradation ◽  
Wide Range ◽  
Pharmaceutical Industries ◽  
Degradation Of Azo Dye

The limited availability of fresh water is a global crisis. The growing consumption of fresh water due to anthropogenic activities has taken its toll on available water resources. Unfortunately, water bodies are still used as sinks for waste water from domestic and industrial sources. Azo dyes account for the majority of all dye stuffs, produced because they are extensively used in the textile, paper, food, leather, cosmetics, and pharmaceutical industries. Bacterial degradation of azo dyes under certain environmental conditions has gained momentum as a method of treatment, as these are inexpensive, eco-friendly, and can be applied to wide range of such complex dyes. The enzymatic approach has attracted much interest with regard to degradation of azo dyes from wastewater. The oxido-reductive enzymes are responsible for generating highly reactive free radicals that undergo complex series of spontaneous cleavage reactions, due to the susceptibility of enzymes to inactivation in the presence of the other chemicals. The oxidoreductive enzymes, such as lignin peroxidase, laccases, tyrosinase, azoreductase, riboflavin reductive, polyphenol oxidase, and aminopyrine n-demethylase, have been mainly utilized in the bacterial degradation of azo dye. Along with the reductive enzymes, some investigators have demonstrated the involvement in some other enzymes, such as Lignin peroxides and other enzymes. This chapter reviews the importance of enzymes in dye degradation.

scholarly journals Photocatalytic activity of Ni0.5Zn0.5Fe2O4@polyaniline decorated BiOCl for azo dye degradation under visible light – integrated role and degradation kinetics interpretation

RSC Advances ◽  
2019 ◽  
Vol 9 (16) ◽  
pp. 8977-8993 ◽  
Author(s):  
Ruchika Tanwar ◽  
Uttam Kumar Mandal
Keyword(s):  
Photocatalytic Activity ◽  
Regression Analysis ◽  
Kinetic Model ◽  
Visible Light ◽  
Azo Dye ◽  
Dye Degradation ◽  
Degradation Kinetics

The photocatalytic activity of BiOCl is tuned through heterogeneous decoration with an integrated Ni0.5Zn0.5Fe2O4@polyaniline. The outstanding degradation capacity, effects of parameters on degradation kinetics and a kinetic model using regression analysis is reported.

scholarly journals Synthesis of stable gold nanoparticles using linear polyethyleneimines and catalysis of both anionic and cationic azo dye degradation

2020 ◽  
Vol 1 (7) ◽  
pp. 2407-2417
Author(s):  
Ozge Cavuslar ◽  
Emre Nakay ◽  
Umut Kazakoglu ◽  
Sirous Khabbaz Abkenar ◽  
Cleva W. Ow-Yang ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Azo Dye ◽  
Dye Degradation ◽  
Direct Reduction ◽  
Anionic Dyes ◽  
Effective Catalyst

Small, stable cationic GNPs were produced by direct reduction of auric acid with linear PEI in water, and used as an effective catalyst for degradation of both cationic and anionic dyes.

scholarly journals Decolorization of Orange-G Aqueous Solutions over C60/MCM-41 Photocatalysts

2019 ◽  
Vol 9 (9) ◽  
pp. 1958 ◽  
Author(s):  
John Kyriakopoulos ◽  
Eleana Kordouli ◽  
Kyriakos Bourikas ◽  
Christos Kordulis ◽  
Alexis Lycourghiotis
Keyword(s):  
Ascorbic Acid ◽  
Azo Dye ◽  
Dye Degradation ◽  
Dye Adsorption ◽  
Fullerene C60 ◽  
Ordered Mesoporous Silica ◽  
Semiconducting Materials ◽  
Ordered Mesoporous ◽  
Orange G ◽  
Mcm 41

The majority of the photocatalysts studied for azo-dye degradation are based on semiconductor materials. Studies reported on non-semiconducting materials are very scarce. In the present work, we studied the fullerene (C60) ability to accelerate photodegradation of the dye’s azo bond in the presence of ascorbic acid. A series of C60 supported on ordered mesoporous silica (MCM-41) catalysts, containing 1, 3, 6, 9, and 12 wt % of fullerene C60, was studied using Orange G (OG) as representative azo-dye. This study showed that partial decolorization is achieved in the dark by simple adsorption of the dye on the bare surface of the carrier. The extent of decolorization increases with the irradiation of the suspension due to photocatalytic degradation of the azo-bond. This is maximized over the sample containing 3 wt % of C60 and it has been attributed to the best combination of the extent of the dye adsorption with the high intrinsic photocatalytic activity of small C60 clusters predominated in this sample. This catalyst proved to be quite stable upon five subsequent photocatalytic cycles, losing less than 5% of its initial activity. No degradation of OG takes place in the absence of ascorbic acid.

Sign in / Sign up

Export Citation Format

Share Document