UV/Fenton净化甲苯气体的研究

Study on degradation of gaseous toluene by UV/Fenton oxidation

挥发性有机物(VOCs)作为化工、印刷等多行业生产过程中极易产生的气体污染物亟需净化治理。实验选择甲苯作为一种典型的VOCs污染物,采用UV/Fenton法耦合湿法洗涤技术净化甲苯气体。考察了H_(2)O_(2)和Fe^(2+)浓度以及初始pH值对甲苯气体净化率的影响,分析了反应过程中甲苯、CO_(2)、H_(2)O_(2)、Fe^(2+)和·OH浓度的变化趋势。结果表明,在最佳反应条件:H2O2浓度为50 mmol/L,Fe^(2+)浓度为2.5 mmol/L,初始pH值为3,UV254 nm功率为6 W,甲苯气体质量浓度为670 mg/m^(3),流量为900 mL/min时,甲苯净化率和矿化率最高,分别达到72%和69%;UV照射促进了Fe^(3+)还原为Fe^(2+),产生大量·OH,显著地提升了甲苯气体的净化率和矿化率。

Volatile organic compounds(VOCs)need to be treated urgently,which are easily produced in the production process of chemical and printing industries.The gaseous toluene,one of the typical VOCs pollutants,was treated by UV/Fenton coupled with wet scrubbing technology.The influences of concentrations of H_(2)O_(2),Fe^(2+)and initial pH on the degradation efficiency of toluene were investigated.The trends of toluene,CO_(2),H_(2)O_(2),Fe^(2+)and·OH concentrations were analyzed.The results show that the optimal condition was:H_(2)O_(2)50 mmol/L,Fe^(2+)2.5 mmol/L,initial pH=3,gaseous toluene concentration 670 mg/m^(3),flow rate 900 mL/min.In this condition,the degradation and mineralization efficiency of gaseous toluene reached 72%and 69%,respectively.UV irradiation can effectively promote the reduction from Fe^(3+)to Fe^(2+)and produce more·OH,which can effectively improve the degradation and mineralization efficiency of gaseous toluene.