Decomposition of toxic pollutants in landfill leachate by ozone after coagulation treatment.
Decomposition of toxic pollutants in landfill leachate by ozone after coagulation treatment.
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DOI：
10.1016/j.jhazmat.2007.07.098
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发表时间：
2008-04
影响因子：
13.6
通讯作者：
T. Poznyak;G. Bautista;I. Chairez;R. Ivan Córdova;L. Rios
中科院分区：
文献类型：
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作者：
T. Poznyak;G. Bautista;I. Chairez;R. Ivan Córdova;L. Rios
研究了墨西哥城Bordo Poniente垃圾卫生填埋场渗滤液（包括生活垃圾和工业垃圾）经Fe 2（SO 4）3（2.5g/L，pH 4-5）混凝处理后，臭氧氧化处理后有机物的评价。混凝处理后腐殖物质的含量降低了70%。然后对初始COD为1511 mg/L、pH为8.5的固体渗滤液进行臭氧处理。通过紫外可见光谱和HPLC技术分析了水溶液样品。用苯、氯仿：甲醇（2：1）和己烷对初始和臭氧化渗滤液进行萃取后，对有机物的初始组成以及中间体和最终产物进行了部分鉴定。然后用带质量检测器和FID的气相色谱仪分析提取物。在HPLC结果中，我们鉴别出了丙二酸和草酸。初始浓度分别为19 mg/L和214 mg/L。草酸在臭氧氧化过程中形成并积累。所获得的结果表明，在臭氧化5 min期间，颜色在100%处消失（视觉上）。氯仿-甲醇萃取的有机物在15 min内就可被臭氧氧化破坏，苯萃取的有机物在5 min内就被臭氧氧化完全，正己烷萃取的有机物臭氧氧化率较低。渗滤液中的有毒物质在15 min的臭氧氧化过程中完全降解。应用简化的数学模型和递归最小二乘法，利用MATLAB6.5程序计算了各组有机物的臭氧化速率常数（作为观测常数）。
This study deals with evaluation of organic matter from Mexico City waste sanitary landfill leachate of Bordo Poniente (including domestic and industrial) by ozonation after a coagulation treatment with Fe2(SO4)3(2.5g/L at pH 4–5). The content of humic substances after the coagulation treatment decreases up to 70%. Then leachate obtained from a solid with initial COD=1511mg/L and the pH 8.5 was treated by ozone. The aqueous samples by a UV–vis and HPLC technique were analyzed. The partial identification of the initial composition of the organic matter as well as of intermediates and final products was carried out after the extraction of the initial and ozonated leachate with benzene, chloroform:methanol (2:1) and hexane. Then the extracts with a gas chromatograph with mass detector and FID were analyzed. In the HPLC results we identify malonic and oxalic acids. The initial concentrations of these acids were 19mg/L and 214mg/L, respectively. The oxalic acid is formatted and accumulated in ozonation. The obtained results show that the color disappears (visually) at 100% during 5min of ozonation. The organic substances, extracted with chloroform–methanol, may be destructed during 15min of ozonation; the organic matter, extracted with benzene, destructs completely by ozone during 5min, and the organic compounds extracted with hexane have a low ozonation rate. The toxic compounds presented in leachate decompose completely during 15min of ozonation. The ozonation rate constants for each group of organics (as observed constants) were calculated applying simplified mathematical model and the recurrent least square method using the program MATLAB 6.5.