Removal of Chlorophenols from Water by Photocatalytic Oxidation

1991 ◽  
Vol 23 (1-3) ◽  
pp. 377-387 ◽  
Author(s):  
J. M. Tseng ◽  
C. P. Huang
Keyword(s):  
Organic Compounds ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Maximum Level ◽  
Order Reaction ◽  
First Order Reaction ◽  
First Order ◽  
Mineral Acids ◽  
Positive Holes

Photocatalyst, TiO2, upon irradiation with uv light produces electrons and positive holes. The positive holes are strong oxidation agents that can oxidize organic compounds such as chlorophenol to mineral acids e.g. HC1 and CO2. Factors such as pH, chlorophenol concentration, concentration of TiO2 and inorganic electrolytes that may affect the oxidation of chlorophenol were investigated. The rate of the chlorophenol oxidation follows a first order reaction with respect to the chlorophenol concentration and independent of pH. The rate increases with concentration of TiO2, reaches a maximum level at 3 g/L then decreases to a constant value upon further increase in TiO2. Increasing the degree of chlorination appears to increase the extent and the rate of oxidation. For mono-chlorophenols the extent of oxidation follows: 4-chloro > 3-chloro > 2-chloro phenol. For dichlorophenols, the order is 2,6-dichloro ≈ 2,5-dichloro > 2,4-dichloro≈ 2,3-dichlorophenol. For symmetrical chlorophenols, the oxidation increases in the order: 4-chloro > 2,5-dichloro > 2,4,6-trichlorophenol. Pentachlorophenol is rapidly decomposed but the extent of oxidation is not complete.

Interactions of hypochlorite ion and humic acid: photolytic and photocatalytic pathways

2001 ◽  
Vol 44 (5) ◽  
pp. 205-210 ◽  
Author(s):  
D. Gonenç ◽  
M. Bekbolet
Keyword(s):  
Humic Acid ◽  
Reaction Kinetics ◽  
Removal Efficiency ◽  
Photocatalytic Oxidation ◽  
Removal Rate ◽  
Order Reaction ◽  
First Order Reaction ◽  
Acid Oxidation ◽  
First Order ◽  
Toc Removal

Photolytic and photocatalytic interactions of hypochlorite ion and humic acid are investigated under various conditions. Humic acid oxidation by aqueous chlorine under dark conditions are expressed in terms of first order reaction kinetics. Upon irradiation (300 nm < λ < 400 nm), photolysis of aqueous chlorine affect the removal efficiency of humic acid via oxidation. TiO2 sensitised photocatalytic oxidation conditions reveal an increase in the TOC removal rate of humic acid in the presence of aqueous chlorine. Under the specified conditions, increasing the photocatalyst loading up to 1.0 mg/mL markedly increase the TOC removal rate.

Synthesis and Properties of 1-(2-Methyl-3-benzothiophene)-2-[2-methyl-5-(3-fluoro-4-chloro)phenyl-3-thienyl]perfluorocyclopentene

2014 ◽  
Vol 1078 ◽  
pp. 98-101
Author(s):  
Guan Ming Liao ◽  
Chun Hong Zheng ◽  
Shou Zhi Pu
Keyword(s):  
Absorption Band ◽  
Emission Intensity ◽  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
Fluorescent Properties ◽  
Visible Absorption ◽  
First Order ◽  
Photostationary State ◽  
Closed Ring

An asymmetrical photochromic diarylethene1-(2-Methyl-3-benzothiophene)-2-[2-methyl-5-(3-fluoro-4-chloro) phenyl-3-thienyl] perfluorocyclopentene (1o) was synthesized and its phtochromic, fluorescent properties were investigated in detail. This compound exhibited remarkable photochromism, upon irradiation with 297 nm UV light, the colorless solution of 1o turned to violetred with a new visible absorption band centered at 538 nm (ε = 1.17 × 104 L mol-1 cm-1) attributable to the closed-ring isomer 1c. The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively. Moreover, diarylethene 1o also exhibited obviously fluorescence switches along with the photochromism.The emission intensity of diarylethene 1o in a photostationary state was quenched to ca. 27% in hexane.

Synthesizes and Properties Research of a Photochromic Diarylethene Bearing a Hexatomic Ring

2013 ◽  
Vol 830 ◽  
pp. 278-281
Author(s):  
Zhi Yuan Sun ◽  
Wei Wei Geng ◽  
Shou Zhi Pu
Keyword(s):  
Reaction Kinetics ◽  
Fluorescence Intensity ◽  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
First Order ◽  
Solid Films ◽  
Kinetics Of

A new photochromic diarylethene compound 1-(2-cyan-3-phenyl)-2-[5-(4-cyanobenzene) -2-methyl-3-thienyl] perfluorocyclopentene was synthesized. And their properties inculding photochromis, fluorescence in both hexane and solid films, reaction kinetics of cyclization and cycloreversion were studied. And its absorption maxima were observed at 539 nm in hexane and at 552 nm in PMMA films, respectively, upon irradiation with 313 nm UV light. The fluorescence intensity of diarylethene decreased upon irradiation with 313 nm UV light. Besides, the cyclization and cycloreversion processes of the compound were determined to be the zeroth and first order reaction by UV-Vis spectra, respectively.

Study on Photochromic Materials with Synthesizes and Properties of a Novel Unsymmetrical Photochromic Diarylethene

2013 ◽  
Vol 327 ◽  
pp. 78-82
Author(s):  
Zhi Yuan Sun ◽  
Xiao Dan Zhang ◽  
Shi Qiang Cui ◽  
Shou Zhi Pu
Keyword(s):  
Methyl Methacrylate ◽  
Absorption Maximum ◽  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
Pmma Film ◽  
First Order ◽  
Open Ring ◽  
Photochromic Materials ◽  
Hexane Solution

A novel unsymmetrical photochromic diarylethene 1-(2-methyl-3-benzofuran)-2-[5-(2-methylbenzene)-2-methyl-3-thieny perfluorocyclopentene1owas synthesized, then its photochromic, Kinetics and fluorescence properties were investigated. The results showed that the diarylethene compound had good photochromism upon irradiation with 297 nm UV light, in which the absorption maximum were observed at 510 nm in hexane solution and 524 nm in poly methyl methacrylate (PMMA) film. Besides, the cyclization and cycloreversion process of the compound were determined to be the zeroth and first order reaction by UV-Vis spectra, respectively. And, the open-ring isomer of the diarylethene exhibited relatively stronger fluorescence at 427 nm when excited at 273 nm in hexane solution.

Synethesis and Properties of 1-(2-trifluoromethylphenyl)-2-[2-methyl-5-(3-N,N-dimethylphenyl)-3-thienyperfluorocyclopentene

2013 ◽  
Vol 473 ◽  
pp. 77-80
Author(s):  
Zhi Yuan Sun ◽  
Dan Dan Xue ◽  
Shou Zhi Pu
Keyword(s):  
Reaction Kinetics ◽  
Fluorescence Intensity ◽  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
Fluorescent Properties ◽  
First Order ◽  
Kinetics Of

An unsymmetrical photochromic diarylethene 1-(2-trifluoromethylphenyl)-2-[2-methyl-5-(3-N,N-dimethylphenyl)-3-thienyperfluorocyclopentene (1a) was synthesized and its photochromism, fluorescent properties and reaction kinetics of cyclization and cycloreversion were studied in detail. The compound exhibited remarkable photochromism and its absorption maxima were observed at 552 nm in hexane and at 569 nm in PMMA films upon irradiation with 297 nm UV light. The fluorescence intensity of diarylethene decreased upon irradiation with 297 nm UV light. In addiation, reaction kinetics of the cyclization and cycloreversion processes of the compound were determined to be the zeroth and first order reaction by UV-Vis spectra, respectively.

Kinetic, Thermodynamic Studies for Photo Degradation of Glibinclamide Drug

2021 ◽  
pp. 4987-4990
Author(s):  
Amel S. Mahdi ◽  
Barakat A. F. Kamel ◽  
Athraa S. Ahmed ◽  
Kafi M. Dawood
Keyword(s):  
Thermodynamic Properties ◽  
Reaction Kinetic ◽  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
Photo Degradation ◽  
Thermodynamic Studies ◽  
First Order ◽  
Degradation Reaction ◽  
Spontaneous Reaction

In this work the photo degradation of glibinclamide is studied by UV light and different concentrations using solvents (water and ethanol) and different times. The reaction kinetic is studied and found that the photo degradation reaction of glibinclamide is (first-order) reaction and the thermodynamic properties (ΔHo, ΔSo and ΔGo) for glibinclamide were calculated and it was found to be (endothermic and spontaneous reaction).

Synthesizes and Properties Research of a Photochromic Diarylethene Bearing a Ethynyl Moiety

2014 ◽  
Vol 952 ◽  
pp. 79-83
Author(s):  
Feng Xia Sun ◽  
Shi Qiang Cui ◽  
Shou Zhi Pu
Keyword(s):  
Reaction Kinetics ◽  
Uv Light ◽  
Amorphous Film ◽  
Order Reaction ◽  
First Order Reaction ◽  
Fluorescence Properties ◽  
Zeroth Order ◽  
First Order ◽  
Photochromic Reaction

A new unsymmetrical photochromic diarylethene compound, 1-(2-Methyl-3-benzothiophene)-2-(5-(4-ethynyl)-2-methylthiophen-3-yl)Perfluorocyclopentene (1o),was synthesized and its photochemical, fluorescence properties were investigated systematically both in solution and PMMA amorphous film. The results showed that this compound exhibited reversible photochromism, changing from colorless to pink after irradiation with 297 nm UV light both in solution and in PMMA amorphous film. The photochromic reaction kinetics indicated that the cyclization processes of 1 belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction.

Research on Photochromic Materials with Synthesis and Properties of 1-(3,5-Dimethyl-4-isoxazolyl)-2-[2-methyl-5-(p-ethoxyphenyl)-3-thienyl]perfluorocyclopentene

2014 ◽  
Vol 1003 ◽  
pp. 27-30
Author(s):  
Guan Ming Liao ◽  
Dan Dan Xue ◽  
Chun Hong Zheng ◽  
Shou Zhi Pu
Keyword(s):  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
Photochromic Properties ◽  
First Order ◽  
Photochromic Materials ◽  
Hexane Solution

An asymmetrical photochromic diarylethene 1-(3,5-Dimethyl-4-isoxazolyl)-2-[2-methyl-5-(p-ethoxyphenyl)-3-thienyl] perfluorocyclopentene (1o) was synthesized and its photochromic properties were investigated. Upon irradiation with 297 nm UV light, 1o exhibited photochromism in hexane solution. The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively. Moreover, diarylethene 1o also exhibited obviously fluorescence switches along with the photochromism.

Synthesis and Photochromism Studies of 1-(2-methyl-3-benzothiophene)-2-[2-methyl-5-(4-aminomethanephenyl)-3-thienyl]perfluorocyclopentene

2014 ◽  
Vol 886 ◽  
pp. 143-146
Author(s):  
Xiao Rong Dong ◽  
Sha Sha Wei ◽  
Gang Liu ◽  
Shou Zhi Pu
Keyword(s):  
Reaction Kinetics ◽  
Uv Light ◽  
Order Reaction ◽  
First Order Reaction ◽  
Acetonitrile Solution ◽  
Zeroth Order ◽  
Photochromic Properties ◽  
First Order ◽  
Fluorescence Switching ◽  
Photochromic Reaction

A new unsymmetrical photochromic diarylethene compound, 1-(2-methyl-3-benzothiophene)-2-[2-methyl-5-(4-aminomethanephenyl)-3-thienyperfluorocyclopentene (1a) was synthesized, its photochromic properties were examined, the result indicated that the Diarylethene 1a changed the color from colorless to purple upon irradiation with 297 nm UV light, in which absorption maxima were observed at 564 in acetonitrile. The photochromic reaction kinetics indicated that the cyclization processes of 1a belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction. This new photochromic system also exhibited fluorescence switching in acetonitrile solution.

Research on Photochromic Compounds with Synthesis and Photochromism of 1-(2-methyl-3-benzofuryl)-2-{2-methyl-5-[4-formyloxyethyl (Rhodamine-B)] phenyl-3-thienyl} Perfluoroyclopentene

2014 ◽  
Vol 1003 ◽  
pp. 55-58
Author(s):  
Dan Dan Xue ◽  
Guan Ming Liao ◽  
Chun Hong Zheng ◽  
Shou Zhi Pu
Keyword(s):  
Visible Light ◽  
Rhodamine B ◽  
Uv Light ◽  
Amorphous Film ◽  
Order Reaction ◽  
First Order Reaction ◽  
Pmma Film ◽  
Photochromic Properties ◽  
Photochromic Compounds ◽  
First Order

A new photochromic diarylethene compound bearing a rhodamine B unit, 1-(2-methyl-3-benzofuryl)-2-{2-methyl-5-[4-formyloxyethyl (rhodamine-B)] phenyl-3-thienyl} perfluorocyclopentene (1o) was synthesized, and its photochromic properties such as photochromism in solution as well as in a polymethylmethacrylate (PMMA) amorphous film were investigated specfically. 1o exhibits good photochromism upon alternating irradiation with UV light and visible light (> 510 nm) in hexane and a PMMA film. The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively.

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