Hartlieb N, Marschner B, Klein W
Fraunhofer-Institut für Umweltchemie und Oekotoxikologie, Schmallenberg, Germany.
Sci Total Environ. 2001 Oct 20;278(1-3):1-10. doi: 10.1016/s0048-9697(01)00902-0.
Composting of municipal biowaste in the presence of 14C-labelled organic contaminants was studied in an attempt to characterize the mobilization potential of dissolved organic matter (DOM) for hydrophobic contaminants. The properties and transformation of DOM extracted from municipal biowaste compost with 10 mM KCl at six stages during 370 days of composting were investigated. DOM was fractionated into molecular weight fractions by ultrafiltration, and DOM structure was studied using CPMAS 13C-NMR- and UV-spectroscopy. The distribution of 14C-labelled model substances (DEHP, pyrene, simazine) upon molecular weight fractions was investigated by ultrafiltration, and association to DOM was studied performing flocculation experiments. The binding capacity of DOM for the model substances was of secondary influence for the mobilization because the intense biochemical reactions during composting pre-dominated the fate of the substances. Composting favoured the degradation of model substances to polar metabolites and supported their binding to the DOM matrix. DEHP and simazine were mainly found in the low- to medium-molecular DOM fraction and showed a small amount of DOM-associated radioactivity (approx. 10%). Pyrene and its metabolites had high affinities to high-molecular DOM. However, a direct relationship between DOM-quality and enhancement of pyrene solubility was not visible. After 120 days of composting DOM showed the highest binding capacity for hydrophobic contaminants.
研究了在存在14C标记有机污染物的情况下城市生物废物的堆肥过程，以表征溶解有机物（DOM）对疏水性污染物的迁移潜力。研究了在370天堆肥过程中的六个阶段，用10 mM KCl从城市生物废物堆肥中提取的DOM的性质和转化。通过超滤将DOM分离成分子量级分，并使用CPMAS 13C-NMR和紫外光谱研究DOM的结构。通过超滤研究了14C标记的模型物质（邻苯二甲酸二（2-乙基己基）酯、芘、西玛津）在分子量级分上的分布，并通过絮凝实验研究了其与DOM的缔合。DOM对模型物质的结合能力对迁移的影响较小，因为堆肥过程中强烈的生化反应主导了物质的归宿。堆肥有利于模型物质降解为极性代谢物，并促进它们与DOM基质的结合。邻苯二甲酸二（2-乙基己基）酯和西玛津主要存在于低至中等分子量的DOM级分中，且与DOM相关的放射性较少（约10%）。芘及其代谢物对高分子量DOM具有高亲和力。然而，未观察到DOM质量与芘溶解度增强之间的直接关系。堆肥120天后，DOM对疏水性污染物的结合能力最高。
