Optimization of parameters applied to degradation and mineralization of p-nitrophenol using advanced oxidative processes

Advanced oxidative processes are widely used in the degradation of organic compounds. The degradation and mineralization of the PNF was evaluated by means of an experimental factorial design, using photolysis (UV) and photo-peroxidation (UV/H2O2). With the results optimized, degradation kinetics was performed and the experimental data adjusted to mathematical models. In the UV system, it was possible to degrade just over 65% and mineralize 15% over 7 h of reaction; however, with the addition of the oxidizing agent H2O2, it was possible to obtain 100% removal of the contaminant, suggesting that there was no formation of intermediate compounds. Kinetics results fitting the first order model and the velocity constants revealed that degradation is extremely faster in the UV/H2O2 system (k1,UV/H2O2 = 0.0580 min− 1 > k1,UV = 0.0018 min− 1).