Abstract: The influences of carbonate on the photodegradation of tetracycline is expounded systematically,through kinetics and radicals analyses. It is found that the presence of carbonate can greatly facilitate the photodegradation of tetracycline. This is mainly attributed to two reasons:the hydroxyl produced from carbonate hydrolysis can improve the productive rate of hydroxyl radicals in the system,and the alkaline environment established can change the existence form of tetracycline,making the photodegradation of tetracycline accomplish easily. On the other hand,carbonate can react with hydroxyl radicals to generate carbonate radicals,leading to the decrease of tetracycline photodegradation rate.

Key words: carbonate, tetracycline, antibiotics, photodegradation, environmental fate

摘要： 从动力学和自由基分析两方面系统阐明了碳酸根对四环素光降解的影响。研究发现，碳酸根的存在能极大促进四环素的光降解。这主要归因于两方面原因：碳酸根水解产生的氢氧根能提高体系中羟基自由基的产率，同时形成的碱性环境能够改变四环素分子的存在形式，使四环素更易发生光降解；另一方面，碳酸根与羟基自由基发生反应生成碳酸根自由基，降低四环素的光降解速率。

关键词: 碳酸根, 四环素, 抗生素, 光降解, 环境归趋

CLC Number: 

• TQ034

• X703