Highly concentrated phenolic wastewater treatment by heterogeneous and homogeneous photocatalysis : mechanism study by FTIR-ATR

• Published in: Water science and technology Vol. 44; no. 5; pp. 229 - 236
• Main Authors: ARANA, J, TELLO-RENDON, E, DONA-RODRIGUEZ, J. M, VALDES DO CAMPO, C, HERRERA-MELLDAN, J. A, GONZALEZ-DIAZ, O, PEREZ-PENA, J
• Format: Conference Proceeding Journal Article
• Language: English
• Published: London IWA 01-01-2001; IWA Publishing
• Subjects: Applied sciences; Aqueous solutions; Carboxylates; Catalysis; Catalysts; Chromatography, High Pressure Liquid; Coloring Agents - chemistry; Degradation; Exact sciences and technology; Formates; Free radicals; High-performance liquid chromatography; HPLC; Hydrogen Peroxide - chemistry; Hydroxyl Radical - chemistry; Industrial wastewaters; Intermediates; Iron - chemistry; Liquid chromatography; Organic chemistry; Oxidation-Reduction; Phenolic compounds; Phenols; Phenols - chemistry; Photocatalysis; Photochemistry; Pollution; Polymers; Spectroscopy, Fourier Transform Infrared; Titanium - chemistry; Titanium dioxide; Waste Disposal, Fluid - methods; Wastewater treatment; Wastewaters; Water treatment and pollution; Fourier transformation; Photocatalysis; Photochemical reaction; Experimental study; Titanium Oxides; Infrared spectrometry; Heterogeneous catalysis; Phenol; Ultraviolet radiation; Industrial waste water; Homogeneous catalysis; Fenton reaction; Physicochemical purification; Oxidation; Waste water purification; Organic compounds
• ISBN: 1843394022; 9781843394020
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2001.0292

The degradation of high phenol concentrations (1 g/L) in water solutions by TiO2 photocatalysis and the photo-Fenton reaction has been studied. From the obtained data it may be suggested that degradation of phenol by TiO2-UV takes place onto the catalyst surface by means of peroxo-compounds formation. At low phenol concentrations other mechanism, the insertion of OH. radicals, may be favored. On the other hand, highly concentrated phenol aqueous solutions treatment by the photo-Fenton reaction gives rise to the formation of polyphenolic polymers. These seem to reduce the process rate. Degradation intermediates have been identified by HPLC and FTIR. The FTIR study of the catalyst surface has shown infrared bands attributable to different chemisorbed peroxo-compounds, formates, ortho-formates and carboxylates that can inactivate the catalyst.