Initial photocatalytic degradation intermediates/pathways of 17α-ethynylestradiol: Effect of pH and methanol

Photocatalytic is one of the inexpensive and non-toxic techniques for degradation of organic pollutants into harmless substances such as water and carbon dioxide. In this study, simple electrolysis method was used in preparation of Ag/TiO2 and α-Fe2O3/HY catalysts. The physicochemical properties of the catalysts were studied using XRD, FTIR, FESEM-EDX and surface area analysis. The pH of solution plays an important role in the photocatalytic degradation of organic pollutants which influences the surface-charge properties of the catalysts. Ag/TiO2 and α-Fe2O3/HY were used as catalyst on degradation of 2-chlorophenol (2-CP) and methyl orange (MO), respectively. The effect of pH on degradation of 2-CP and MO were investigated over a pH range from 2 to 9. Higher degradation of 2-CP and MO were obtained at pH 5 (74%) and pH 2 (80%), respectively. This finding might be explained by the amphoteric performance of the catalyst using point zero charge (pHZPC). The pHZPC for Ag/TiO2 and α-Fe2O3/HY was found to be at pH 6.3 and pH 7.2, respectively. Hence, the activities of the catalysts may have been affected by the existence of a strong electrostatic field between the positively charged catalysts surface and negatively charged 2-CP and MO caused a pH value lower than their pHZPC give greater degradation.

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Microplastic pollution reduction by a carbon and nitrogen-doped TiO2: Effect of pH and temperature in the photocatalytic degradation process

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2020.122632 ◽

2020 ◽

Vol 395 ◽

pp. 122632 ◽

Cited By ~ 14

Author(s):

Maria Camila Ariza-Tarazona ◽

Juan Francisco Villarreal-Chiu ◽

Juan Manuel Hernández-López ◽

Javier Rivera De la Rosa ◽

Virginia Barbieri ◽

...

Keyword(s):

Photocatalytic Degradation ◽

Degradation Process ◽

Pollution Reduction ◽

Effect Of Ph ◽

Doped Tio2 ◽

Carbon And Nitrogen ◽

Nitrogen Doped

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Unveiling New Degradation Intermediates/Pathways from the Photocatalytic Degradation of Microcystin-LR

Environmental Science & Technology ◽

10.1021/es801637z ◽

2008 ◽

Vol 42 (23) ◽

pp. 8877-8883 ◽

Cited By ~ 128

Author(s):

Maria G. Antoniou ◽

Jody A. Shoemaker ◽

Armah A. de la Cruz ◽

Dionysios D. Dionysiou

Keyword(s):

Photocatalytic Degradation ◽

Degradation Intermediates

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Effect of Isopropanol on Microstructure and Activity of TiO2Films with Dominant {001} Facets for Photocatalytic Degradation of Bezafibrate

International Journal of Photoenergy ◽

10.1155/2014/490264 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 17

Author(s):

Murtaza Sayed ◽

Fu Pingfeng ◽

Hasan M. Khan ◽

Pengyi Zhang

Keyword(s):

Photocatalytic Activity ◽

Photocatalytic Degradation ◽

Hydroxyl Radicals ◽

Terephthalic Acid ◽

Hydrothermal Solution ◽

Titanium Sheet ◽

Fluoride Ions ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass ◽

Degradation Intermediates

Titanium dioxide (TiO2) films with dominant {001} facets coated on a titanium sheet (Ti) were synthesized with the simple hydrothermal method by using Ti as the precursor and substrate. The effect of addition of isopropanol into the hydrothermal solution on the structure, photocatalytic activity, and stability of as-synthesized TiO2films was investigated. The presence of isopropanol obviously influenced the microstructure of as-synthesized TiO2films, which was converted from microspheres into irregular close stack of truncated tetrahedrons. And the percentage of exposed {001} facets calculated from the Raman spectra increased from 48.2% to 57%. Accordingly, the TiO2films prepared with addition of isopropanol showed high and stable photocatalytic activity, which is nearly 2.6 times as that of the conventional P25 TiO2coated on Ti-substrate. In addition, the photocatalytic activity of as-synthesized TiO2films was greatly enhanced after calcination treatment at 600°C, which can be attributed to removal of fluoride ions and organic residuals adsorbed on the surface of the catalyst. Photoluminescence (PL) technique was used for the detection of produced hydroxyl radicals (•OH) on the surface of UV-illuminated TiO2using terephthalic acid as probe molecule. The photocatalytic degradation intermediates of bezafibrate were analyzed by an ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and accordingly the degradation pathways were proposed.

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