Studies On Photodegradation And Biodegradation Of Chlorpyrifos In Aqueous Water

The direct photolysis of chlorpyrifos in aqueous solution irradiated by high pressure mercury lamp (HPML), ultraviolet light(UV) and sunlight were investigated. Effects of pH and H₂O₂ on photodegradation of chlorpyrifos were studied under HPML. The possible photo-products and pathway were found out. Also, the biodegradation of Chlorpyrifos by microbe D3 and D1 were studied. The biodegradation of Chlorpyrifos by microbe D3 in different concentrations and the biodegradation of Chlorpyrifos in different concentrations by microbe D3 were studied too.1. The photolysis half life of chlorpyrifos in aqueous solution under HPML, UV and sunlight was 53. 32min, 431. 43min, 1407. 7min respectively.2. Under the irradiation of HPML, the photolysis rate constant of chlorpyrifos remained consistent from acid conditions to netrual condition and increased in alkaline conditions.3. Within 5-15mmol/L, with the increasing concentration of H₂O₂ ,the speed of photodegradation of chlorpyrifos were increasing. When the concentration was 25mmol/L, the speed of photodegradation dropped instead. The half life of chlorpyrifos was 34.16 min.4.There were 3 kinds of photo-products detected by HPTLC. One of the might pathway of photodegradation was5. The half life of biodegradation of chlorpyrifos of 20mg/L by microbe D1 and D3 was 50. 06h,10. 45h respectively.6. The half life of biodegradation of chlorpyrifos of 10, 20, 30mg/L by microbe D3 was 8. 07h, 10. 69h, 13. 03h respectively.7. The half life of biodegradation of chlorpyrifos of 20mg/L by microbe D3 of cfu=0. 24×10¹⁰, cfu=1. 2×10¹⁰, cfu=2. 4×10¹⁰ was 12. 17h, 10. 58h, 9. 86h respectively．...