Degradation Kinetics of Diclofenac in Water by Fenton’s Oxidation

Abstract

An extensively used non-steroidal anti-inflammatory drug (NAID) diclofenac (DCF) is reported to be present in the environment. Several adverse effects have been reported due to presence of DCF and hence it should be removed from the environment. Among several treatment methods, classic Fenton oxidation is found to be an effective process for the removal of organic contaminants. In the present study, the effect of initial DCF concentration and pseudo second order rate constants of DCF degradation are evaluated by Fenton oxidation process. Percent DCF reduction and percent Chemical Oxygen Demand (COD) removal are measured as the objective parameters to be maximized. At the optimum conditions, for 31.43 x 10-3 mM of initial DCF concentration, 74.25 percent DCF reduction and 72.80 percent COD removal are observed in 240 minutes reaction time. The pseudo second order rate constants are 206.95 M-1S-1 for 31.43 x 10-3 mM and 75.55 M-1S-1 for 157.17 x 10-3 mM initial concentration of DCF. The Fenton oxidation process is the most effective in degradation of DCF in water.