光助芬顿反应催化降解气体中甲苯

以甲苯作为挥发性有机污染物(VOCs)的代表,利用连续进气动态实验装置,研究光助芬顿反应降解气体中甲苯的作用.考察了芬顿试剂溶液初始p H、H2O2浓度、Fe2+浓度以及甲苯初始浓度对降解甲苯的影响,并利用在线质谱和色谱对产物进行了定性、定量分析.结果表明,紫外光照加快了羟基自由基的生成,显著提高了气体中甲苯的去除率;p H=3.0、H2O2浓度为20 mmol·L-1、Fe2+浓度为0.3 mmol·L-1的条件下,甲苯去除率最高;当甲苯初始浓度为260 mg·m-3时,去除率能够达到98%;光助芬顿反应催化降解气体中甲苯实验未检测到CO2之外的中间产物,CO2产率分析表明去除的甲苯全部转化为CO2.

Photocatalytic Degradation of Gaseous Toluene by a Photo-Fenton Reaction

In this study, the performance of photo-Fenton reaction on decomposition of toluene was investigated by a flowing column using toluene as a representative of volatile organic pollutants (VOCs).The effects of initial pH, H₂O₂ concentration, Fe²⁺ concentration, initial concentration of toluene on degradation of toluene by photo-Fenton reaction were evaluated.Mass spectrometry and gas chromatograph were utilized to detect the products.The results showed that the introduction of UV greatly enhanced the Fenton reaction by improving the generation of hydroxyl radicals.When the initial concentration of toluene was 260mg·m^-3, the toluene removal can achieve 98% under the following experimental conditions: initial pH=3.0, H₂O₂ 20 mmol·L^-1, Fe²⁺ 0.3 mmol·L^-1.Furthermore, no other intermediate except CO₂ was detected in the reaction that photocatalytic degradation of toluene in waste gas by the photo-Fenton, which indicates all the degraded toluene was mineralized into CO₂.