| 不同形态无机氮对水中微量药物安替比林光降解效能影响 |
| 摘要点击 1618 全文点击 972 投稿时间：2012-10-26 修订日期：2012-11-29 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 安替比林 光降解 NH4+ NO2- NO3- pE |
| 英文关键词 antipyrine(ANT) photodegradation ammonium nitrite nitrate pE |
|
| 中文摘要 |
| 在300 W氙灯光照条件下,研究了消炎镇痛类药物安替比林(ANT)在纯水中的光降解效能与机制,重点考察了水中不同形态无机氮及pE值对ANT光降解效能的影响. 结果表明,ANT在不同条件下的光降解均符合假一级反应动力学; ANT在纯水中的光降解包括直接光解以及由羟基自由基(·OH)和单线态氧(1O2)参与的自敏化光解,贡献率分别为55.27%、22.19%和22.54%. 不同形态无机氮(NH4+、NO2-和NO3-)单独存在条件下对ANT光降解效能的影响差异较大. 在pE值较低时,即无机氮主要以NH4+形式存在,对ANT的光降解几乎没有影响; 随着pE值的升高(由4.82~6.85),NH4+向NO2-转化,由于NO2-不仅能与ANT竞争吸收光子,同时还对·OH具有较强的淬灭作用,使得其对ANT光降解的抑制作用逐渐增强,当pE值达到6.85,即无机氮主要以NO2-形式存在时,ANT光降解的抑制率达到最高为35.31%; 随着pE值的继续升高(由6.85~8.15),NO2-向NO转化,对ANT光降解的抑制作用逐渐减弱. |
| 英文摘要 |
| The photodegradation performance and mechanisms of antipyrine (ANT, a member of anti-inflammatory analgesics) under simulated irradiation using a 300 W Xenon lamp were explored in this study. And the variation of the photodegradation of ANT in the presence of different forms of nitrogen and different pE values in the aqueous environment were also investigated. The results demonstrated that ANT photodegradation proceeds via pseudo first-order kinetics in all cases. Photodegradation of ANT in water occurs through direct photodegradation and self-sensitization via reactions with hydroxyl radical (·OH) and singlet oxygen (1O2). Presence of different forms of inorganic nitrogen (NH4+, NO2- and NO3-) showed rather different effects. At low pE value (<5), NH4+ was the main form of inorganic nitrogen, and little effect was observed on ANT photodegradation. With the increase of pE value from 4.82 to 6.85, nitrogen form changed from NH4+ to NO2- accordingly, and the inhibiting effect increased gradually due to their competitive absorption for the irradiation and NO2- acting as a scavenger of·OH. At pE 6.85, NO2- was the main form of inorganic nitrogen, which showed a maximum inhibiting rate of 35.31%. When the pE value continued to increase from 6.85 to 8.15, the nitrogen form changed from NO2- to NO3-, and the suppression effect on ANT photodegradation decreased. |
|
|
|
