摘要
针对传统工艺难以去除水中的农药微污染问题,采用超声波工艺降解有机磷农药乐果,研究了超声波频率、功率、初始浓度、初始pH值、无机离子及腐植酸对乐果去除率的影响。结果表明,超声波降解乐果最佳频率为600 kHz;降解速率常数随着输出功率增加而提高,随初始浓度增大而减小;溶液中无机离子对降解速率有不同影响,HCO3-和CO32-具有抑制作用,Br-和Fe2+具有促进作用;初始溶液中的腐植酸会降低反应速率,且随着腐植酸浓度的增加,其抑制作用加强;在反应初始阶段,较低pH有利于乐果降解。试验证明超声波可以有效去除水中残余乐果。
The presence of phosphorus pesticides in the aquatic environment has raised concerns due to its poor degradation in conventional water treatment plants.Sonolytic degradation of dimethoate in aqueous solution was investigated.The effects of ultrasonic frequency and power,dimethoate＇s initial concentration and initial pH value,and the concentration of humic acid and different ions on its degradation rate were studied.The results indicated that 600 kHz is the optimal frequency for dimethoate degradation and the degradation rate of dimethoate increases with the enhancement of input power and the decrease of initial concentration.The added inorganic ions can contribute diverse effects on the degradation.Carbonate and bicarbonate ions have negative effecst while bromonium and ferrous ions have positive effects.During the initial period,lower pH value is favorable,however,the constant of degradation rate decreases as the concentration of pre-existing humic acid increases.It is proved that sonolytic process has great potential for the removal of dimethoate.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2011年第1期208-213,共6页
Journal of Sichuan University (Engineering Science Edition)
基金
国家自然科学基金资助项目(50878163
50708067)
国家科技重大专项资助项目(2008ZX07421-002)
国家高技术研究发展计划("863")资助项目(2008AA06A412)
关键词
超声降解
乐果
动力学
sonolytic degradation
dimethoate
kinetics
