DBD耦合针铁矿降解苯模拟废气

Decomposing Benzene Using Dielectric Barrier Discharge with Goethite

采用双介质阻挡放电(DBD)研究针铁矿煅烧温度、负载量、输入能量、停留时间、初始浓度及湿度对等离子体催化降解苯的影响,分析降解产物及碳氧化物选择性,并对降解机理进行探究。研究表明,在该等离子体发生装置下,最佳条件为煅烧温度350℃、负载量4.0%、停留时间1.408 s、相对湿度70%左右。在输入能量为1 242 J/L、初始浓度为400 mg/m^3时,相对单独DBD,针铁矿的加入将苯的降解率从62.00%提升至73.36%,臭氧浓度从132.8 mg/m^3降至36.8 mg/m^3,碳氧化物选择性从67.13%提升至82.14%,出口NO_2浓度从7.95 mg/m^3降低至1.70 mg/m^3。利用FT-IR、GC-MS分析降解产物,发现最终产物主要为CO_2、CO、O_3、微量NO_2及少量硝基苯酚、苯醌等。

The effects of calcination temperature,loading,input energy,residence time,initial concentration and humidity on the degradation of benzene by plasma were investigated using coaxial dielectric barrier discharge. The degradation products and the selectivity of carbon oxides were analyzed. And the mechanism of degradation was explored. The results showed that the optimal conditions were calcination temperature 350 ℃,loading capacity 4%,residence time 1.408 s,relative humidity 70%,under the condition of the plasma generator. When the input energy was 1 242 J/L and the initial concentration was 400 mg/m^3,the addition of goethite increased the degradation rate of benzene from 62.00% to 73.36%,and the ozone concentration decreased from 132.8 mg/m^3 to 36.8 mg/m^3, the selectivity of carbon oxides increased from 67.13% to 82.14%,and the export NO_2 concentration decreased from 7.95 mg/m^3 to 1.70 mg/m^3. The products were analyzed by FT-IR and GC-MS. The final products were CO_2,CO,O_3,a small amount of nitrophenol and benzoquinone, etc.