Kinetics analysis of Wet Air Oxidation of Fosfomycin Pharmaceutical Wastewater

High concentration of fosfomycin pharmaceutical wastewater was treated by wet air oxidation (WAO). The kinetic characteristics of the removal of total organic phosphorus (TOP) and chemical oxygen demand (COD_Cr) in WAO of fosfomycin pharmaceutical wastewater were investigated. The effects of reaction temperature and oxygen partial pressure on TOP and COD_Cr removal were quantified. The results showed that the removal of COD_Cr and TOP in WAO was divided into fast and slow reaction steps and the removal process was well accorded with piecewise first-order kinetic model. Generally, the removal rates of TOP and COD_Cr increased with increasing reaction temperature and oxygen partial pressure in both fast and slow reaction steps, and the removal rates of the slow reaction step were found to be less sensitive to reaction temperature and oxygen partial pressure. According to Arrhenius equation, the activated energies for TOP oxidation were Ea_fast 68.6 and Ea_slow 44.7 kJ/mol, and for COD_Cr removal were Ea_fast 41.0 and Ea_slow 24.5 kJ/mol at 1.0 MPa oxygen partial pressure.