摘要
采用臭氧氧化的方法对微囊藻毒素-RR(MC-RR)进行降解.结果表明,在O3∶MC-RR(物质量比)为6的条件下,MC-RR的去除率最高可达到83.0%;pH上升、水中NOM含量增加都能显著降低MC-RR的臭氧降解效果.使用HPLC-MS考察了MC-RR的臭氧降解产物,并在此基础上探讨了MC-RR的臭氧氧化降解途径:主要通过Adda途径和Mdha途径来完成对MC-RR的降解和脱毒作用.臭氧氧化的Adda途径是通过对MC-RR上Adda侧链的进攻,断开具有活性的Adda支链,而达到脱毒的目的,其中Adda途径过程中的苯环羟基化作用对整个过程有促进作用;臭氧氧化的Mdha途径是通过对MC-RR肽环上面Mdha和Ala的断键,打开环状肽链,使藻毒素失去活性.在整个过程中Adda途径占主导地位.
Degradation of algal toxin Microcystin-RR （MC-RR） by ozonation processes was investigated. The degradation rate of MC- RR reached 83. 0% at ozone/MC-RR dosage of 6,and the degradation efficiency was decreased with increase of pH or NOM contents. Ozonation byproducts of MC-RR under different ozone dosages were detected by HPLC-MS to elucidate degradation mechanisms and pathways. The results showed that MC-RR degradation by attacking of ozone and hydrogen radicals mainly involved in substitution and cleavage of the Adda conjugated diene structure,cleavage of the peptide bond between Mdha and Ala. And Adda degradation pathway exerted a dominant position during the process.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2010年第5期1239-1245,共7页
Environmental Science
基金
高等学校科技创新工程重大项目培育资金项目(708048)
江苏省环境工程重点实验室开放基金项目(KF2009002)
