气液介质阻挡放电降膜反应器降解甲硝唑实验研究

针对抗生素药物甲硝唑难生物降解的难题,首次借助气液冷等离子体高级氧化的方法,采用连续气液介质阻挡放电降膜反应器对其进行降解实验研究.同时,定量测量和评价了反应器的·OH氧化能力,考察了不同初始浓度、不同放电气氛及加入叔丁醇对甲硝唑降解效果的影响,并重点探讨了·OH对甲硝唑降解的作用.结果表明,当甲硝唑在反应器内停留时间为3 s时,初始浓度为5、10和20 mg·L~(-1)的甲硝唑溶液的转化率分别为97.8%、85.4%和78.7%,说明气液介质阻挡放电降膜反应器对甲硝唑具有显著的氧化降解能力.同时实验进一步发现,氧化反应过程中·OH对甲硝唑的降解具有重要贡献.

Degradation of metronidazole using a gas-liquid dielectric barrier discharge falling film reactor

Advanced oxidation method based on cold plasma technique was proposed to enhance the biodegradability of antibiotics metronidazole. A continuous gas-liquid dielectric barrier discharge (DBD) falling film reactor was used to degrade the metronidazole. Firstly,quantitative measurement and evaluation of ·OH oxidation ability of the reactor were conducted. On this basis,experimental analysis of the metronidazole degradation in the reactor was conducted to examine the effect of initial concentration,discharge atmosphere,and tert-butanol addition on metronidazole degradation,especially the effect of ·OH on metronidazole degradation. The results showed that when the residence time of metronidazole in the reactor was 3 s,the conversion rate of the metronidazole with initial concentration of 5,10 and 20 mg·L^-1 was 97.8%,85.4% and 78.7%,respectively. This indicated that the gas-liquid DBD falling film reactor has significant oxidative ability for metronidazole degradation. Meanwhile,it was further found that ·OH had an important contribution to the oxidation reaction process for metronidazole degradation.