电子束辐照降解水体中的金霉素

摘要

应用电子加速器辐照研究了去除水体中金霉素(30mg/L)的过程,初步探索了剂量、不同气氛条件下叔丁醇的存在、pH值、无机阴离子等对去除效率的影响.然后根据实验结果推测了降解机理和降解产物毒性.结果表明:电子束辐照能高效去除水体中的金霉素,且还原性粒子占主导作用;pH 值为碱性时利于金霉素的去除;0.005mol/LCO32-、SO42-、NO3-或Cl-的存在能促进其去除.根据超高效液相色谱-质谱(UHPLC-MS)对降解产物的分析,并结合理论计算推测出10种降解产物和相应的降解途径.之后的费氏弧菌毒理实验数据显示:降解后水样的生物毒性随着吸收剂量先增高后缓慢降低,但辐照5.0kGy后毒性依然较大.%The process of removing chlorotetracycline (CTC) 30mg/L in aqueous solution was preliminarily explored by electron beam irradiation (EBI). Several factors such as dose, the existence of tert-butyl alcohol under different atmosphere conditions, initial pH and inorganic salts affecting on the removal efficiency were examined. Degradation mechanism and the toxicity of degradation products were proposed through experimental data. The experiment results show that:EB irradiation can effectively remove CTC from water, and the reduction radicals play the key role; It was more effective when pH is alkaline; the presence of 0.005mol/LCO32-、SO42-、NO3- or Cl- promotes the degradation. Ten kinds of possible degradation products and corresponding degradation pathways were deduced from the analysis of the degradation products by ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) with the assistance of theoretical calculation results. Finally, the toxicity test of Vibrio fernuli shows that the toxicity of the irradiated intermediates increases firstly and then decrease slowly, however, it is still toxic at the absorption dose of 5.0kGy.