Radiation induced degradation of Congo red dye: a mechanistic study

Abstract Synthetic dyes are persistent pollutants with poor biodegradability. The present study is about the degradation of direct Congo red dye in aqueous media using the Co-60 gamma radiation source. The experimental conditions such as gamma-ray absorbed doses, amount of oxidant (H2O2) and pH conditions were evaluated. The λmax of dye solution was noted as 498 nm, and then, decrease in absorbance and reduction in chemical oxygen demand (COD) were examined. The complete colour removal of dye was observed at 5 kGy, while a significant COD removal was observed at 15 kGy gamma-ray absorbed dose in conjunction with oxidant for 50 mg/L concentration. It was found that pH has no influence on degradation efficiency. A possible degradation pathway was proposed. The radiolytic end products were monitored by Fourier transform infrared (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS) to explore the degradation mechanism. It was imperative to study the oxidative degradation pathway to provide directions for potential applicability of advanced oxidation process (AOP) in industrial wastewater treatment.

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Plausible Applicability of Aqueous Congo Red Dye System as Secondary Gamma-ray Dosimeter

E-Journal of Chemistry ◽

10.1155/2008/809362 ◽

2008 ◽

Vol 5 (3) ◽

pp. 572-576

Author(s):

I. Das Sarma ◽

D. V. Parwate

Keyword(s):

Extinction Coefficient ◽

Congo Red ◽

Gamma Ray ◽

Molar Extinction Coefficient ◽

Aqueous Systems ◽

Γ Irradiation ◽

Gamma Source ◽

Congo Red Dye ◽

Red Dye ◽

Dye Solutions

Aqueous congo red dye solutions in the concentration range of 0.01–0.03mM were irradiated for varying γ doses 0.050 kGy to 0.150 kGy. The molar extinction coefficient of the dye solution of congo red was found to be 2.70×105at its absorption maxima 499.0 nm. No change in λmaxwas observed on irradiation. As the dye solutions are sensitive towards γ–irradiation, decolouration occurs on irradiation. The G–values for the doses in between the range of 0.035 kGy to 0.125 kGy were found to be practically constant for pure aqueous systems. Hence this was used to determine the dose of the gamma source. With the addition of alcohols in the systems, degradation of the dyes due to radiations decreased considerably.

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Decolourization of Congo Red Dye using Solar/H2O2 Process

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.22924 ◽

2021 ◽

Vol 33 (6) ◽

pp. 1294-1298

Author(s):

R. Raja ◽

A. Rose Venis ◽

R. Tamil Selvan ◽

T. Mohandas

Keyword(s):

Light Intensity ◽

Congo Red ◽

Advanced Oxidation Process ◽

Kinetic Studies ◽

Solar Light ◽

H2o2 Concentration ◽

Congo Red Dye ◽

Toc Removal ◽

Red Dye ◽

Removal Studies

The Congo red dye was decolourized by advanced oxidation process using solar/H2O2 method and the effect of various parameters on decolourization like pH, H2O2 concentration, dye concentration, solar light intensity, additives, COD and TOC removal studies and kinetic studies were investigated. The photodegradation process was done by exposing dye solutions with the concentration of 100 mg/L treated with 50% H2O2 to sunlight with the lux intensity range of 60,000-90,000 lux. The best possible pH 2 with an optimal H2O2 concentration of 1000 mM to achieve 100% decolourization within the period of 5 h. The kinetic studies done on H2O2 concentration also proved that the high solar light intensity leads to higher decolourization and low solar light intensity leads to lesser decolourization. Addition of additives like H2PO4 – and Cl– leads to a decrease in the rate of decolourization. The removal of COD and TOC removal was found to be 83.26% and 5.18%, respectively.

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Evaluation of Cocoa Beans Shell Powder as a Bioadsorbent of Congo Red Dye Aqueous Solutions

Materials ◽

10.3390/ma14112763 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2763

Author(s):

Gabriela Rodríguez-Arellano ◽

Juan Barajas-Fernández ◽

Ricardo García-Alamilla ◽

Laura Mercedes Lagunes-Gálvez ◽

Antonio Hilario Lara-Rivera ◽

...

Keyword(s):

Adsorption Capacity ◽

Congo Red ◽

Industrial Wastes ◽

Cocoa Bean ◽

Synthetic Dyes ◽

Cocoa Beans ◽

Congo Red Dye ◽

Order Polynomial ◽

Red Dye ◽

Shell Powder

The use of synthetic dyes in the textile, leather, and paper industries is a source of groundwater pollution around the world. There are different methods for the treatment of wastewater that has been contaminated with dyes, among which adsorption with agro-industrial wastes is gaining relevance. In the present study, the adsorption capacity of cocoa bean shell powder was evaluated when it was used as a bioadsorbent for Congo red dye in an aqueous medium. A 24 central factorial design with central and axial points was proposed to determine the adsorption capacity. The factors that were studied were the adsorbent (0.06–0.15 g), Congo red (40–120 mg L−1), pH (3–11), and time (4–36 h). The bioadsorbent was characterized through scanning electron microscopy and Fourier-transform infrared spectroscopy. The effects of the factors on the adsorption capacity for Congo red using cocoa bean shell were nonlinear, and they were modeled with a second-order polynomial (p < 0.05) and with an R2 of 0.84. The bioadsorbent obtained a maximum adsorption of 89.96% in runs. The process of optimization by using the surface response allowed the maximization of the adsorption, and the validation showed that 95.79% adsorption of the dye was obtained.

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An effective method for determining the retention and distribution of cellulose nanofibrils in paper handsheets by dye labeling

TAPPI Journal ◽

10.32964/tj17.03.157 ◽

2018 ◽

Vol 17 (03) ◽

pp. 157-164 ◽

Cited By ~ 3

Author(s):

Shengdan Wang ◽

Wenhua Gao ◽

Kefu Chen ◽

Jinsong Zeng ◽

Jun Xu ◽

...

Keyword(s):

Correlation Coefficient ◽

Congo Red ◽

Kraft Pulp ◽

Cellulose Nanofibrils ◽

Standard Curve ◽

Congo Red Dye ◽

Mechanical Disintegration ◽

Softwood Kraft Pulp ◽

White Water ◽

Red Dye

Cellulose nanofibrils (CNF) were prepared by cellulase in conjunction with mechanical disintegration from the bleached softwood kraft pulp and labelled by Congo red dye. The labelled CNF were used to investigate the retention and distribution of CNF in paper handsheets. The retention of the labelled CNF was obtained by measuring the absorbance of white water using an ultraviolet-visible spectrophotometer. The results showed that this method for measuring the retention was rapid, feasible, and sensitive, owing to the high correlation coefficient R2 (0.9993) of the standard curve. The labelled CNF showed even distribution in paper handsheets. The colorimetric values of paper handsheets were explored with a residual ink analyzer.

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Degradation of Congo Red Dye in Aqueous Solution by Using Phytoremediation Potential of Chara Vulgaris

Chitkara Chemistry Review ◽

10.15415/ccr.2013.11005 ◽

2013 ◽

Vol 1 (1) ◽

pp. 67-75 ◽

Cited By ~ 7

Author(s):

Pooja Mahajan ◽

Jyotsna Kaushal

Keyword(s):

Aqueous Solution ◽

Congo Red ◽

Chara Vulgaris ◽

Congo Red Dye ◽

Red Dye

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Catalytic influence of iron loaded sba-15 for the photodegradation of congo red dye

International Journal of Pharma and Bio Sciences ◽

10.22376/ijpbs.2017.8.1.p118-124 ◽

2017 ◽

Vol 8 (1) ◽

Author(s):

A.R. SASIEEKHUMA R ◽

T.SOMANATHA N ◽

M. SHANMUGA M

Keyword(s):

Congo Red ◽

Congo Red Dye ◽

Red Dye

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Functionalization of Congo red dye as a light harvester on solar cell

Open Chemistry ◽

10.1515/chem-2020-0034 ◽

2020 ◽

Vol 18 (1) ◽

pp. 287-294

Author(s):

Harsasi Setyawati ◽

Handoko Darmokoesoemo ◽

Irmina Kris Murwani ◽

Ahmadi Jaya Permana ◽

Faidur Rochman

Keyword(s):

Solar Cell ◽

Congo Red ◽

Large Scale ◽

High Efficiency ◽

Solar Cell Device ◽

Dye Sensitized ◽

Congo Red Dye ◽

Elemental Analyses ◽

Red Dye ◽

Solar Cell Technology

AbstractThe demands of ecofriendly technologies to produce a reliable supply of renewable energy on a large scale remains a challenge. A solar cell based on DSSC (Dye-Sensitized Solar Cell) technology is environmentally friendly and holds the promise of a high efficiency in converting sunlight into electricity. This manuscript describes the development of a light harvester system as a main part of a DSSC. Congo red dye has been functionalized with metals (Fe, Co, Ni), forming a series of complexes that serve as a novel light harvester on the solar cell. Metal-congo red complexes have been characterized by UV-VIS and FTIR spectroscopy, and elemental analyses. The performance of metal complexes in capturing photons from sunlight has been investigated in a solar cell device. The incorporation of metals to congo red successfully improved of the congo red efficiency as follows: Fe(II)-congo red, Co(II)-congo red and Ni(II)-congo red had efficiencies of 8.17%, 6.13% and 2.65%, respectively. This research also discusses the effect of metal ions on the ability of congo red to capture energy from sunlight.

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