Sourwater treatment by fenton process and its effect on phytotoxicity with <i>Lactuca sativa

Abstract

In this work, degradation of stripped sourwater by Fenton´s oxidation process was investigated by a central composite design and response surface methodology. The effects of initial concentrations of H2O2 and Fe2+ on the total phenols degradation was studied in a batch reactor. The optimum total phenols degradation was 92% achieved within an H2O2 concentration of 4.4 g L-1 and iron concentration of 162 mg L-1. The mathematical kinetic model adequately represented the experimental results. The results indicated that the Fenton oxidation rate (1/m) and removal efficiency (1/b) were more dependent on iron concentration than H2O2 concentration. After the Fenton process, the sourwater presented a seed germination rate (L. sativa) above 80%, indicating reduced phytotoxicity of the treated effluent. It was also observed that the H2O2 concentration significantly affected the inhibition concentration (IC50).

Keywords

• petroleum effluent
• advanced oxidative process
• total phenols
• bioassays
• experimental design.