The Study On The Degradation Of Acetaprid In Pesticide Wastewater By The Low-temperature Plasma Using Dielectric Barrier Discharge

Currently, the application research of wastewater treatment by low temperature plasma is still in the trial stage, especially less in research of pesticide wastewater treatment. In the discharge process of low temperature plasma, the electron has very high temperature, but the temperature of heavy particle is far lower than the electron, the system has low temperature. Plasma wastewater treatment is a new wastewater treatment technology combining high-energy electron irradiation, ozonation and ultraviolet decomposition, meanwhile has the physical and chemical effect. As a branch of plasma technology, the study of wastewater degradation using dielectric barrier discharge (DBD) is widely and deeply exploring. As a newly developed technology, DBD has the advantage of producing many active substances (·OH、 O3), high efficiency, good fidelity and can degrade nearly all sorts of organic pollutants without selectivity. Compared with glow discharge plasma, low temperature plasma using DBD has larger discharge space, higher electronic destiny, and longer electrode life, so has great potential in industrial application. This subject studied the treatment of acetamiprid in pesticide wastewater by low temperature plasma which produced by DBD.We studied the different discharge power, initial concentration and the effects of different external factors, such as different catalysts, pH, Na2B4O7(radical scavenger) and electrolytes on acetamiprid degradation. The results showed that when the discharge power was170W, the initial concentration of acetamiprid was50mg/L, and degradation of200min, the removal of acetamiprid reached83%and the rate fitted first-order kinetics. When the addition of the catalyst to the wastewater was at a suitable amount, the number of·OH increased in the wastewater, and the removal rate reached more than85%at the discharge time of125min, thus shortening the reaction time and reducing the energy consumption. The addition of Na2B4O7and electrolytes to the wastewater reduced the amount of·OH, thus inhibiting acetamiprid degradation. The degradation rate was higher in pH=9, and the solution of pH decreased with discharge time increasing.The article studied the influence mechanism of ozone oxidation by adding ozone gas collecting cover and tert-butyl alcohol. We analyzed the structure of acetamiprid degradation products by HPLC-MS and UV, at the same time studied the reaction mechanism and degradation mechanism in acetamiprid degradation process.The results showed that low temperature plasma produced by DBD had a good effect on acetamiprid treatment, and it provided some technical guidance for low temperature plasma technology on industrial applications for pesticide wastewater treatment.