• 关键词：双酚A  无机氮  光降解  pE值

• 基金项目：国家自然科学基金（No.21966030）

• 韩瑶
• 新疆农业大学化学工程学院，乌鲁木齐 830052

• 李丽君
• 中国地质调查局沈阳地质调查中心，沈阳 110032

• 赵荣梅
• 新疆维吾尔自治区药品检验研究院，乌鲁木齐 830052

• 石志立
• 新疆农业大学化学工程学院，乌鲁木齐 830052

• 景伟文
• 新疆农业大学化学工程学院，乌鲁木齐 830052

• 摘要：在紫外光照射条件下，研究了水溶液中不同形态无机氮（NO₃^-、NO₂^-和NH4+）对双酚A（BPA）光解的影响和机制.结果表明，BPA在纯水中的光解包括直接光解和·OH、¹O₂、O₂^.- 等ROS（活性氧物种）参与的自敏化光解反应，其反应均符合准一级动力学模型特征，·OH、¹O₂、O₂^.-、BPA^*相对应的贡献率分别为13.4%、7.7%、22.9%、47.9%，以直接光解途径为主.分别添加的不同形态的无机氮显示出不同的效应，NO₃^-、NO₂^-表现出抑制效应，NH4+则没有影响.当不同形态无机氮共存时，若pE值<5，此时无机氮以NH4+为主，故对BPA光解基本没有影响；随着pE值的增大（4.82~8.15），NH4+逐渐转化为NO₂^-和/或NO₃^-，光解速率常数减小，且NO₃^-和NO₂^-共存时表现出比NH4+和NO₂^-之间更强的拮抗作用.最后利用GC-MS法鉴定了BPA可能的光解产物，发现NO₃^-/NO₂^-单独或共存时均能引发硝代反应.

• Abstract：The impact and mechanism of inorganic nitrogen （NO₃^-， NO₂^-， and NH4+） on the photodegradation of bisphenol A （BPA） was investigated in aqueous media under UV light irradiation. Results suggested that BPA photodegradation in pure water was associated with direct photodegradation and self-sensitized photodegradation involving reactive oxygen species （ROS）， such as ·OH， ¹O_2， and O₂^-，. It was found that BPA photodegradation conformed to pseudo first-order kinetics in all cases and the corresponding contributions of ·OH， ¹O₂， O₂^.-， and BPA^* to BPA photodegradation were 13.4%， 7.7%， 22.9%， and 47.9%， respectively， indicating that the direct photodegradation was the main reaction pathway. Furthermore， the presence of different forms of inorganic nitrogen （NO₃^-， NO₂^- and NH4+） showed different effects on BPA photodegradation. NO₃^- and NO₂^- showed inhibitory effects， whereas NH4+ had no impact. When different forms of inorganic nitrogen coexisted， NH4+ was a dominating inorganic nitrogen at low pE value （<5） and therefore showed little effect on BPA photodegradation. With the increase of pE value from 4.82 to 8.15， NH4+ gradually transformed to NO₂^- and/or NO₃^-， slowing down the photolysis. Additionally， an antagonistic action between NO₂^- and NO₃^- was stronger than that between NH4+ and NO₂^-. Finally， the possible photodegradation products of BPA were identified by GC-MS and it was considered that NO₃^- and NO₂^- could initiate nitration reaction either alone or coexisting.

• Key words：bisphenol A  inorganic nitrogen  photodegradation  pE value

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