堆放垃圾渗滤液水溶性有机物的荧光特性

为揭示堆放垃圾渗滤液物质组成特性及其变化规律,采用三维荧光光谱,对4个不同垃圾堆场渗滤液水溶性有机物(DOM)进行了研究.结果显示,堆放垃圾渗滤液样品S1中含有2类蛋白荧光峰:类酪氨酸荧光峰和类色氨酸荧光峰,其他3个样品(S2、S3及S4)只含有类色氨酸荧光峰,此外还出现了类腐殖质荧光峰,且不同样品中该峰的数目、类型及位置均存在差异,显示渗滤液样品S1只含有类蛋白类物质,而其他3个样品除此之外还含有类腐殖质物质,且腐殖化程度各异.类蛋白类物质-Hg(II)配位研究显示,与类色氨酸荧光峰相比,类酪氨酸荧光峰更易受介质微环境改变影响;室温培养模拟研究显示,与类腐殖质物质相比,类蛋白类物质更易发生降解.三维荧光光谱可以有效表征堆场渗滤液DOM物质组成及其变化规律.

Fluorescence characteristics of dissolved organic matter from dumped waste leachate

In order to reveal the characteristics of composition of leachates from dumped waste and their variations, three-dimensional excitation-emission matrix fluorescence spectroscopy (3DEEM) were applied for dissolved organic matter (DOM) of leachates extracted from four different dumped waste. Leachate sample S1 contained two different kinds of protein-like fluorescence peak, i.e., tyrosine-like and tryptophan-like fluorescence peaks. The other three samples (S2, S3 and S4), however, in addition to tryptophan-like fluorescence, contained humus-like fluorescence peaks as well, and the number, type and location of the peaks were different in according to samples. Leachate samples S1 contained only protein-like matter, while the other three samples contained both humus-like matter and protein-like matter, and the degree of humification of humus-like matter varied in different samples. The complexation between the protein-like matter in sample S1 and Hg (II) indicated that, compared with tryptophan-like fluorescence peak, tyrosine-like fluorescence peak could be more easily impacted by the micro-environmental change; the results of culture experiments at room temperature demonstrated that, protein-like substance could be easily broken, while humus-like substance shown strong resistance to microbe. 3DEEM could be effectively characterized the composition of DOM of leachates from dumped waste and their variations.