title: Photocatalytic degradation of trans-cinnamic, dihydrocinnamic, trans-caffeic, and dihydrocaffeic acids and characterization of the products.
abstract: Catalysed degradation of aqueous solutions of cinnamic 1, dihydrocinnamic 2, dihydrocaffeic 3 and trans-caffeic 4 acids in the presence of (TiO2) and UV radiation and the products identified by HPLC, and after treatment with diazomethane by GC-MS have been studied. A pH range of 3 to 11 was used. The four acids, in the presence of TiO2 in the dark, underwent little degradation. Extended irradiation of all the acids in the presence of TiO2 produced complete degradation as shown by TOC measurements. Initially the volume of carbon dioxide produced rose steadily to a constant value.
authors.affiliation: Centre for Environmental Research, Brunel University, Uxbridge, Middlesex, UB8 3PH, UK. Susan.Grimes@brunel.ac.uk
authors.forename: S M
authors.initials: SM
authors.lastname: Grimes
authors.forename: L K
authors.initials: LK
authors.lastname: Mehta
authors.forename: H C
authors.initials: HC
authors.lastname: Ngwang
mesh_terms: D002109:Caffeic Acids / Q000737:chemistry*; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D010083:Oxidants, Photochemical / Q000737:chemistry; D010777:Photochemistry; D014025:Titanium / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods; D014876:Water Pollution / Q000517:prevention & control
chemical_list: D002109:Caffeic Acids; D002934:Cinnamates; D007220:Industrial Waste; D010083:Oxidants, Photochemical; C029010:cinnamic acid; C009495:titanium dioxide; D014025:Titanium; C040048:caffeic acid