Decomposition Of Ethanethiol And N₂O Using Dielectric Barrier Discharge Combined With 185 Nm UV-light

As an alternative technology, dielectric barrier discharge plasma (DBD) with a large amount of oxidative radicals and low cost is more appropriate for the simultaneous treatment of various pollutants. In the present study, a combination of dielectric barrier discharge plasma with 185 nm UV-light photolysis system (CDBDP) energized by a DBD power supply was constructed to decompose a type of volatile organic sulfur compounds (VOSCs), EtSH, and greenhouse gases, N2O, under room temperature at atmospheric pressure. Gas pollutant removal efficiency and energy efficiency were carefully evaluated as a function of applied voltage, inlet concentration, gas flow rate and relative humidity. Moreover, the mechanism for gas pollutant decomposition under combined plasma with photolysis treatment was proposed.From the experimental study, we can draw the conclusions that EtSH removal efficiency and energy yield can be effectively improved by 10.4%and 0.4 g/kWh of DBD induced with UV-light than bare DBD. EtSH removal efficiency increased along with the RH increased to about 70%, and then decreased when the humidity continue to increase. At the optimal RH was about 70%, EtSH removal efficiency was 90,75 and 12%in CDBDP, DBD and UV system, respectively. The optimum conditions was the gas flow rate of 1.4 m/h, the initial concentration of 150 mg/m and input power was 3.8 W in UV system and 80 W in DBD/CDBDP system, the maximal removal efficiency was 79.85%,69.46%and 10.57%, respectively. DBD induced with UV-light could improve EtSH removal efficiency, energy yield and degradation rate by 10.4%, 0.4 g/kWh and 0.010 W·s·L-1, respectively. The possible reaction pathways were proposed based on the products identified by FT-IR. After DBD treatment, EtSH could produce secondary pollutants such as CO, CO2, O3, SO2. Therefore, it should be use associated with other treatment processes such as alkaline absorption.The paper studied the removal efficiency of mass flow of N2O in CDBDP and DBD system using dielectric barrier discharge. As the experiment showed, when increasing initial N2O concentration and wind velocity, higher removal efficiency was obtained, while it was in proportion to input power. N2O could not be degradated in only UV system. And the removal efficiency of N2O in CDBDP system was obviously better than DBD system. The optimum conditions in the experiment were initial N2O concentration of 60 mg/m, input power of 400 W and flow rate of 0.6 m3/h, while N2O removal efficiency was 73.31 and 67.54% in CDBDP and DBD system, respectively.