A New Photocatalytic System Using Steel Mesh and Cold Cathode Fluorescent Light for the Decolorization of Azo Dye Orange G

High color and organic composition, the effluents from the textile dyeing and finishing industry, can be treated by photocatalytic oxidation with UV/TiO2. The objective of this study was to prepare a new photocatalytic system by coating nanosized TiO2particles on steel mesh support and using cold cathode fluorescent light (CCFL) irradiation at 365 nm in a closed reactor for the oxidation of azo dye C.I. Orange G (OG). Various factors such as reaction time, coating temperature, TiO2dosage, pH, initial dye concentration, and service duration were studied. Results showed efficient color removal of the OG azo dye by the photocatalytic system with TiO2-coated temperature at 150°C. The optimal TiO2dosage for color removal was 60 g m−2. An acidic pH of 2.0 was sufficient for photocatalytic oxidation whereas basic condition was not. The rate of color removal decreased with increase in the initial dye concentration. The TiO2-coated steel mesh can be used repeatedly over 10 times without losing the photocatalytic efficiency. Results of FTIR and IC indicated the breakage of N=N bonds, with sulfate as the major and nitrite and nitrate as the minor products, which implied degradation of dye molecules.

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Supported Zinc Oxide Photocatalyst for Decolorization and Mineralization of Orange G Dye Wastewater under UV365 Irradiation

International Journal of Photoenergy ◽

10.1155/2013/595031 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Ming-Chin Chang ◽

Hung-Yee Shu ◽

Tien-Hsin Tseng ◽

Hsin-Wen Hsu

Keyword(s):

Reaction Time ◽

Azo Dye ◽

Textile Wastewater ◽

Color Removal ◽

Fluorescent Light ◽

Preparation Temperature ◽

Steel Mesh ◽

Toc Removal ◽

Photocatalytic System ◽

Orange G

To solve the environmental challenge of textile wastewater, a UV/ZnO photocatalytic system was proposed. The objective of this study was to prepare a photocatalytic system by utilizing both cold cathode fluorescent light (CCFL) UV irradiation and steel mesh supported ZnO nanoparticles in a closed reactor for the degradation of azo dye C.I. Orange G (OG). Various operating parameters such as reaction time, preparation temperature, mixing speed, ZnO dosage, UV intensity, pH, initial dye concentration, and service duration were studied. Results presented efficient color and total organic carbon (TOC) removal of the OG azo dye by the designed photocatalytic system. The optimal ZnO dosage for color removal was 60 g m−2. An alkaline pH of 11.0 was sufficient for photocatalytic decolorization and mineralization. The rate of color removal decreased with the increase in the initial dye concentration. However, the rate of color removal increased with the increase in the UV intensity. The steel mesh supported ZnO can be used repeatedly over 10 times without losing the color removal efficiency for 120 min reaction time. Results of Fourier transform infrared (FTIR) and ion chromatography (IC) indicated the breakage of N=N bonds and formation of sulfate, nitrate, and nitrite as the major and minor products. The observation indicated degradation of dye molecules.

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Research Progress on Photocatalytic/Photoelectrocatalytic Oxidation of Nitrogen Oxides

Transactions of Tianjin University ◽

10.1007/s12209-021-00293-9 ◽

2021 ◽

Author(s):

Shuangjun Li ◽

Linglong Chen ◽

Zhong Ma ◽

Guisheng Li ◽

Dieqing Zhang

Keyword(s):

Nitrogen Oxides ◽

Photocatalytic Oxidation ◽

Research Progress ◽

Future Directions ◽

Inorganic Semiconductors ◽

Photoelectrocatalytic Oxidation ◽

Low Concentrations ◽

Photocatalytic System ◽

Metal Organic ◽

Oxidation Of No

AbstractThe emission of nitrogen oxides (NOx) increases year by year, causing serious problems to our livelihoods. The photocatalytic oxidation of NOx has attracted more attention recently because of its efficient removal of NOx, especially for low concentrations of NOx. In this review, the mechanism of the photocatalytic oxidation of NOx is described. Then, the recent progress on the development of photocatalysts is reviewed according to the categories of inorganic semiconductors, bismuth-based compounds, nitrogen carbide polymer, and metal organic frameworks (MOFs). In addition, the photoelectrocatalytic oxidation of NOx, a method involving the application of an external voltage on the photocatalytic system to further increase the removal efficiency of NOx, and its progress are summarized. Finally, we outline the remaining challenges and provide our perspectives on the future directions for the photocatalytic oxidation of NOx.

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Evaluation of color removal and degradation of a reactive textile azo dye on nanoporous TiO2 thin-film electrodes

Electrochimica Acta ◽

10.1016/j.electacta.2003.12.057 ◽

2004 ◽

Vol 49 (22-23) ◽

pp. 3807-3820 ◽

Cited By ~ 107

Author(s):

Patricia A. Carneiro ◽

Marly E. Osugi ◽

Jeosadaque J. Sene ◽

Marc.A. Anderson ◽

Maria Valnice Boldrin Zanoni

Keyword(s):

Thin Film ◽

Azo Dye ◽

Tio2 Thin Film ◽

Color Removal ◽

Thin Film Electrodes

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Analysis of sonolytic degradation products of azo dye Orange G using liquid chromatography–diode array detection-mass spectrometry

Ultrasonics Sonochemistry ◽

10.1016/j.ultsonch.2011.03.010 ◽

2011 ◽

Vol 18 (5) ◽

pp. 1068-1076 ◽

Cited By ~ 31

Author(s):

Meiqiang Cai ◽

Micong Jin ◽

Linda K. Weavers

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Azo Dye ◽

Degradation Products ◽

Diode Array ◽

Diode Array Detection ◽

Orange G ◽

Array Detection ◽

Sonolytic Degradation

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Photocatalytic degradation of azo dye in TiO2 suspended solution

Water Science & Technology ◽

10.2166/wst.2001.0105 ◽

2001 ◽

Vol 43 (2) ◽

pp. 313-320 ◽

Cited By ~ 11

Author(s):

C.-H. Hung ◽

P.-C. Chiang ◽

C. Yuan ◽

C.-Y. Chou

Keyword(s):

Reaction Time ◽

Light Intensity ◽

Photocatalytic Degradation ◽

Azo Dye ◽

Batch Reactor ◽

Reaction Rates ◽

Pseudo First Order Reaction ◽

Degradation Rates ◽

Orange G ◽

Degradation Of Azo Dye

The photocatalysis of azo dye, Orange G, by P-25 anatase TiO2 was investigated in this research. The experiments were conducted in a batch reactor with TiO2 powder suspension. Four near-UV lamps were used as the light source. The experimental variables included solution pH level, amount of TiO2, illumination light intensity, and reaction time. A pseudo-first order reaction kinetic was proposed to simulate the photocatalytic degradation of Orange G in the batch reactor. More than 80% of 10 mg/L Orange G decomposition in 60-minute reaction time was observed in this study and fast decomposition of Orange G only occurred in the presence of both TiO2 and suitable light energy. Faster degradation of Orange G was achieved under acid conditions. The degradation rates of Orange G at pH = 3.0 were about two times faster than those at pH = 7.0. Faster degradation of azo dye was observed for greater irradiated light intensity and more TiO present during the reaction. The reaction rates were proportional to TiO2concentration and light intensity with the power order of 0.726 and 0.734, respectively.

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Highly efficient degradation of azo dye Orange G using laterite soil as catalyst under irradiation of non-thermal plasma

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2019.01.066 ◽

2019 ◽

Vol 246 ◽

pp. 211-220 ◽

Cited By ~ 12

Author(s):

Jean-Baptiste Tarkwa ◽

Elie Acayanka ◽

Bo Jiang ◽

Nihal Oturan ◽

Georges Y. Kamgang ◽

...

Keyword(s):

Thermal Plasma ◽

Azo Dye ◽

Laterite Soil ◽

Highly Efficient ◽

Orange G ◽

Non Thermal Plasma ◽

Degradation Of Azo Dye

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

Applied Sciences ◽

10.3390/app9091958 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1958 ◽

Cited By ~ 5

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.

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