Degradation of p-hydroxyphenylacetic acid by photoassisted Fenton reaction.
The chemical decomposition of p-hydroxyphenylacetic acid, a phenolic pollutant present in agro-industrial plant effluents, has been investigated by means of the Fenton's reaction and the photoassisted Fenton's reaction, the so-called photo-Fenton system. The degradation levels achieved have been compared to those obtained by applying other Advanced Oxidation Processes, such as the combination UV/H2O2. The optimum pH to carry out the decomposition of this organic compound by either Fenton or photo-Fenton systems was found to be pH = 3. The presence of buffers such as phosphate impedes these processes due to the formation of ferric complexes. A reaction mechanism, which allows calculating the contribution of the radical reaction to the global process, has been proposed. According to this mechanism, the dominant way of degradation of p-hydroxyphenylacetic acid is through its reaction with the OH radicals originated in the photolysis of H2O2 and, especially, in the Fenton's reaction.
Acero
L L
LL
Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, Badajoz, Spain.
Benítez
F J
FJ
Real
F J
FJ
Leal
A I
AI
D002273:Carcinogens / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D017665:Hydroxyl Radical / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D010648:Phenylacetates / Q000737:chemistry*; D014466:Ultraviolet Rays; D014873:Water Pollutants
D002273:Carcinogens; C045076:Fenton's reagent; D005290:Ferric Compounds; D016877:Oxidants; D010648:Phenylacetates; D014873:Water Pollutants; D017665:Hydroxyl Radical; C008070:4-hydroxyphenylacetic acid; D006861:Hydrogen Peroxide; D007501:Iron