Study For Treatment Of RDX Wastewater With Ultrasonic Cavitation/Ultraviolet/Fenton Technology

The treatment of the explosive wastewater is very important, the treatment of thethe RDX in wastewater is particularly important. The wastewater treatment for theRDX wastewater has achieved some success in recent years. However, the RDXcontains nitro, which has dangerous, biological toxicity and chemical stability, andwhich can easily lead to other more toxic intermediates in the degradation process,which makes it very difficult to degrade.The RDX wastewater was degraded withultraviolet (UV)-Fenton, ultrasonic cavitation (US)-Fenton, ultrasonic cavitation plusUV-Fenton at normal temperature.The effect to removal rate of the RDX and CODcrof wastewater of reaction time,the dosage of H₂O₂,the dosage of FeSO₄·7H₂O,pH and initial RDX concentration were investigated, and the optimum condition wasdetermined via orthogonal and factor experiments.The results show that thesynergistic effect of US/UV-Fenton is better than simply under the conditions ofultraviolet irradiation, or a simple ultrasonic cavitation treatment effect on the RDX;but also reduces dosage of H₂O₂ and Fe2+, maintaining hydrogen peroxide andferrousions higher utilization, lower processing cost.The optimum conditions fordealing with RDX as follows: The optimum conditions for dealing with RDX asfollows: under the 60W UV irradiation and ultrasonic frequency is 40kHz, initialRDX concentration at 180 mg/L, H₂O₂ concentration at 10% and dosage at 0.30mL;FeSO₄·7H₂O concentration at 10% and dosage at 0.06mL(FeSO₄·7H₂O volumesatisfying that VFeSO₄·7H₂O/VH₂O₂ is 1:5)ï¼›pH at 3 can reach the best removal efficiencyof RDX as 96.8% and the best removal efficiency of CODcr as 85.0%.