摘要
通过研究臭氧对水中甲基对硫磷的降解,探索臭氧对甲基对硫磷的降解机制和影响因素.将臭氧气体充入反应器中与甲基对硫磷进行反应,采用GC-MS和标准样品对中间产物进行定性分析,并用HPLC同时监测甲基对硫磷的残留量和中间产物的生成量.结果表明,臭氧对甲基对硫磷的降解由臭氧直接氧化和羟基自由基间接氧化共同完成,降解历程遵循假一级反应动力学.50 mmol/L离子清除剂叔丁醇使甲基对硫磷的降解速率降低60%,而溶液pH值对降解速率则无明显影响.通过GC/MS分析,确定了甲基对氧磷为甲基对硫磷的臭氧降解中间产物.甲基对氧磷的生成量受到溶液pH和甲基对硫磷起始浓度的影响,较低溶液pH和较高甲基对硫磷起始浓度均有利于甲基对氧磷的积累,而离子清除剂则对甲基对氧磷的生成量没有显著影响.
Ozonation of methyl mechanism and influencing factors. parathion was investigated to understand the degradation Methyl parathion was oxidized by bubbling ozone gas into a cylindrical glass reactor. Oxidation intermediate of methyl parathion was qualitatively identified by GC/MS, and contents of methyl parathion residue and intermediate were detected by HPLC. Degradation of methyl parathion by ozone followed the pseudo-first-order reaction through ozone direct oxidation and hydroxyl radical indirect oxidation. Scavenger tert-butyl alcohol (TBA) (50 mmol/L) significantly decreased the degradation rate constant of methyl parathion (60%), while solution pH affected the degradation insignificantly. Methyl paraoxon was identified as ozonation intermediate of methyl parathion. Formation of methyl paraoxon favored low solution pH and high initial concentration of methyl parathion, but be insignificantly influenced by TBA during ozonation.
出处
《湖北大学学报(自然科学版)》
CAS
北大核心
2009年第2期197-200,共4页
Journal of Hubei University:Natural Science
基金
中山大学-香港理工大学联合研究基金(A-PD94)
广东省自然科学基金(07300488)资助
关键词
甲基对硫磷
甲基对氧磷
臭氧
降解
methvl parathion methyl paraoxon ozone
degradation