Degradation of a mixture of pollutants in water using the UV/H2O2 process

WATER SCIENCE AND TECHNOLOGY

I W A PUBLISHING

Año: 2010 p. 3026 - 3032

0273-1223

The degradation reaction of a simple mixture of pollutants (dichloroacetic acid + formic acid)employing H2O2 and UVC radiation (253.7 nm) has been studied in a well-mixed reactor whichoperates inside a recycling system. The aim of this work is to develop a systematic methodologyfor treating degradation of mixtures of pollutants, starting from a rather manageable system tomore complex aggregates. In this contribution, the effects of different variables such as hydrogenperoxide/pollutant mixture initial concentration ratio, pH and incident radiation at the reactor wallwere studied. The results show that the best degrading conditions are: pH ¼ 3.5 and hydrogenperoxide concentrations from 3.9 to 11.8mM (134–400 mg/L), for initial concentrations of 1.10and 0.39mM for formic acid and dichoroacetic acid respectively (50 mg/L for both pollutants).The influence of the incident radiation at the reactor wall on the degradation rates of the mixtureis significant. In addition to this, it has been shown that in the employed aqueous solution nostable reaction intermediates are formed. On this basis, a complete reaction scheme for themixture is proposed that is suitable for a reaction kinetics mathematical modeling of the mixtureand further studies of increasing complexity.