Ozone / Hydrogen Peroxide Degradation Of Rdx Wastewater

Comparative experiments of ozonation and O₃/H₂O₂ process were conducted with RDX as the model organic pollutant. It was found that O₃/H₂O₂ process greatly increased the removal efficiency of RDX and COD compared with that achieved by ozonation alone. It was believed that reactions with OH radicals would be the major pathways for the oxidative transformation of RDX, even when conventional ozonation was applied. The influence of several different parameters including the concentration of simulated wastewater, reaction time, pH, H₂O₂ and ozone flux was investigated in the O₃/H₂O₂ process eliminating RDX experiment systematically. The optimum treatment conditions of eliminating 100mL simulated wastewater of RDX were as follows: reaction time was 40min; H₂O₂(30%): 0.3mL; ozone flux: 0.9L/min; pH:ll. In the optimum treatment conditions of the O3/H2O2 process eliminating RDX experiment, the removal efficiency of RDX was 96.8% and the removal efficiency of COD was 92.4%。 The precision tests demonstrated the efficiency of oxidation of RDX employing the O₃/H₂O₂ process was almost constant. The kinetics of oxidation of RDX was also studied. It found that the degradation of simulated wastewater of RDX could be described by a pseudo-first-order kinetics. A by-product was tentatively identified as 1,3-dinitro-1,3,5-triazacyclohex-5-ene by GC-MS. The degradation efficiency of three kinds of actual wastewaters of RDX and seven kinds of simulated wastewaters of explosives under the optimum treatment conditions was satisfactory.