Oxidation Of Phenolic And Azole Wastewater By Dielectric Barrier Discharge Plasma And Parameter Optimization

A mass of pesticides wastewater was produced in China every year as the huge demand for pesticides.The dielectric barrier discharge plasma is generated by high frequency and voltage power supply.The target pollutants can be degraded through the active groups in the plasma.This article is aimed at developing an efficient,rapid approach with non-thermal plasma(NTP).The main idea could be interpreted as following:A set of device of dielectric barrier discharge(DBD)plasma was developed to degrade phenol in aqueous and these parameters were optimized.The concentration of phenol was measured by HPLC.The results showed that the system achieves best results on condition that in faintly acid environment(pH=5),voltage of 10kV and the solution flow rate of 60ml/min.Several gas atmosphere(Ar,air,O2)was operated.In the presence of inhibitor of · OH,the degradation of phenol reduced nearly 30%,and the exist of CC14 that consume the · H leads to little increase in efficiency.Based on the actual phenol pesticide tailwater of a chemical plant,the degradation efficiency of phenol by DBD-NTP system was studied.The concentration of phenol was reduced from 4.8mg/L to 0.2mg/L,and the other pollutants in index were also disposed well.The degradation efficiency of tricyclazole(TC)and 1,2,4-triazole(Tz),and optimum operating parameters were also studied.The removal rate reached 98%and 54%on condition in pH of 5,voltage of 10kV and frequency of 10kHz.The effects of the flow rate of air entering the system were investigated,and it achieved the best results when it was l00ml/min.The concentration of O3 and H2O2 were respectively measured by the method of iodimetry and titanium sulfate spectrophotometry to be gradually increasing,and the concentration of H2O2 reduced in the later stage.The TC vulnerable sites were calculated by the DFT and intermediates were measured by GC-MS,for speculating the degradation mechanism and sequence of TC by DBD-NTP system.The article shows the DBD-NTP possessing unique advantages that is efficiently and rapidly in the treatment of highly toxic refractory organic compounds.It is further proved that NTP technology has wide application prospect and utilization value in industrial wastewater,especially pesticide wastewater treatment.