School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
Environ Sci Pollut Res Int. 2018 Jan;25(1):290-298. doi: 10.1007/s11356-017-0320-8. Epub 2017 Oct 15.
To decrease the secondary pollution of volatile organic compounds (VOCs) during adsorbent regeneration by microwave, electrodeless lamp was added in the microwave field to oxidize VOCs in the gas phase. Ultraviolet has a significant improvement on mineralization of VOCs generated from adsorbate during adsorbent regeneration. However, the mechanism and main influence factors on the degradation of VOCs are not clear. The effect of microwave power, regeneration time, airflow rate, and humidity content on the mineralization of adsorbed tetracycline during adsorbent regeneration was studied. Ozone concentration and ultraviolet irradiation intensity were also measured to analyze the mechanism of the microwave-ultraviolet adsorbent regeneration method. Although the electrodeless lamp adsorbed microwave and competed with the regenerated adsorbent, the mineralization percentage of tetracycline increased about 10% with the presence of electrodeless lamp at the same microwave power supply. Besides, humidity content also takes an important role on enhancing the mineralization of tetracycline. The mineralization of tetracycline in the microwave-ultraviolet field consists of three major parts: pyrolysis, ozone oxidation, and free radical oxidation. More than 50% adsorbed tetracycline can be oxidized into HO and CO during regeneration in 5 min. These results support the potential use of electrodeless lamp to treat VOCs in the gas phase to decrease the risk of secondary pollution during adsorbent regeneration.
为了降低吸附剂再生过程中微波对挥发性有机化合物（VOCs）的二次污染，在微波场中加入无电极灯以氧化气相中的 VOCs。紫外线对吸附剂再生过程中吸附质产生的 VOCs 的矿化具有显著的改善作用。然而，对于 VOCs 的降解机制和主要影响因素尚不清楚。研究了微波功率、再生时间、气流速率和湿度含量对吸附四环素在吸附剂再生过程中矿化的影响。还测量了臭氧浓度和紫外线辐照强度，以分析微波-紫外线吸附剂再生方法的机理。尽管无电极灯吸附了微波并与再生的吸附剂竞争，但在相同的微波电源下存在无电极灯时，四环素的矿化率增加了约 10%。此外，湿度含量对增强四环素的矿化也起着重要作用。在微波-紫外线场中，四环素的矿化由三个主要部分组成：热解、臭氧氧化和自由基氧化。在 5 分钟的再生过程中，超过 50%的吸附四环素可以氧化成 HO 和 CO。这些结果支持使用无电极灯处理气相中的 VOCs，以降低吸附剂再生过程中二次污染的风险。
