ABSTRACT
This article presents the results of the degradation of clofibric acid by ozonation. Furthermore, results of the toxic effect of clofibric acid and its intermediate compound, 4-chlorophene generated during the oxidation process, to alga Selenastrum capricornium, are also discussed. The degradation and mineralization of the compound are studied according to the optimized operating conditions. These variables include pH, conductivity, hydraulic retention time and the use of a mixing maze. All the trials are conducted in a purpose-built pilot-scale reactor. Working under the optimal operating conditions (pH = 9, HRT = 12.5 min and ozone dose = 14 ± 2 gN/m3), a degradation value of 98% was obtained, although mineralization of the compound did not occur. Results show that clofibric acid and its intermediate are toxic during the first 10 min of treatment for concentrations equal to or greater than 1 mg/L. Under optimal conditions toxicity is not observed for any concentrations.
Acknowledgments
The authors wish to express their gratitude to Mr. Alvaro Valenzuela Romero, at Zonosistem Ingeniería del Ozono, S.L, for his contributions in carrying out this study.
Funding
This work was partially funded by the Spanish Ministry of Education and Science through I+D Project CTM2008-04940/TECNO.