乐果UV-TiO_2光催化降解产物对LGX9敏感菌株的毒性  

Effect of the effluents resulted in the UV-TiO_2 photocatalytic degradation process of dimethoate on the toxicity growth of bacteria Bacillus cereus LGX9

作　　者：杜银花[1] 王欣[1] 王金翠[1] 刘宝林[1] 

机构地区：[1]上海理工大学食品质量与安全研究所,上海200093

出　　处：《安全与环境学报》2014年第5期335-339,共5页Journal of Safety and Environment

基　　金：上海市自然科学基金项目(10ZR1420700);上海市研究生创新基金项目(JWCXSL1102)

摘　　要：为准确反映乐果UV-TiO2光催化液对环境生物的毒性作用,以乐果敏感菌株LGX9为受试对象,研究了TiO2、H2O2、Fe2+、通入空气、初始pH值等因素对乐果UV-TiO2光催化液降解率及抑菌率的影响规律。结果表明,当乐果初始质量浓度为200 mg/L、反应温度为30℃时,在反应体系TiO2质量浓度1.0 g/L、H2O2浓度0.025 mol/L、Fe2+浓度0.002 mol/L,且以3.5 L/min通入空气、初始pH值为1的条件下,反应1 h后,乐果降解率为92.70%,对LGX9菌株生长已无抑制作用。研究表明,利用乐果敏感菌株LGX9可以有效反映乐果光催化降解液对环境的毒性作用。The paper intends to introduce our study results on the effects of the effluents resulted in the UV - TiO2 photocatalytic degrada- tion process of dimethoate on the toxicity growth of bacteria Bacillus cereus LGX9. Our study results indicate that the UV - TiO2 process can serve as a useful tool for treating pesticide pollutants in aqueous solution. Due to the facts that some intermediates in the photocatalytic reaction turn to be toxic or even severely toxic and more recalcitrant than the original pollutants, the toxicity of the mixture of intermediates formulated as the chemical products have actually been more seriously evaluated and treated. In this paper, we would like to focus our attention on the toxicity of the effluents formed during the UV - TiO2 photocatalytic degradation process of dimethoate. Since the photodegradation experiments can be done inside a illuminated photocatalytic reactor with a light source of 365 nm, 450 W mercury lamp. We have done our investigation and experiments by choosing our initial concentration of dimethoate in a dosage of 200 mg/L, at a reaction temperature of 30 ℃. And then keep watching the testing effects of TiO2, H2O2, Fe2＋ , the bubbling air and the initial pH value on the growth of a dimethoate toxicity-sensitive bacteria named Bacillus cereus LGX9, which can be isolated from the farm soil, while the minealisation efficiency can be determined by the phosphomolybdehum blue spectropbotometric method. Finally, both the toxicity and the minealisation efficiency of the photocatalytic degradation effluents can be found significantly affected by the photodegradation conditions. The results indicate that the bubbling air or adding H2O2 and Fe2＋ to the reaction products were favorable for the degradation, on the condition that there exist suitable TiO2 concentration and pH value. The effluents would be non-toxlc to the growth of Bacillus cereus LGX9 when judged by biomass measurement, if the photocatalytic degradation of dimethoate would be conducted under the following o

关 键 词：环境科学技术基础学科 敏感菌株 乐果 光催化降解 毒性 

分 类 号：X172[环境科学与工程—环境科学]