Chromatographic Approach to Environmental Science of Dioxins

该项目的目标包括：(1)开发水中废弃物中二恶英和多氯联苯的光解方法；(2)开发一种高效液相色谱法高选择性分离二恶英异构体和多氯联苯同族物的方法；(3)开发一种新型假固定相，用于高速高选择性EKC分离环境污染物，即疏水烃和卤代芳香族化合物。(1)将多氯联苯从水溶液中成功吸附到填充在石英柱中的疏水固定相上，柱外紫外线照射使其光解。所有的多氯联苯在2-丙醇-水混合物中可以在几个小时内完全光解，只有亲水产物离开色谱柱。毒性更强的共面多氯联苯的光解速度比邻位取代多氯联苯慢。然而，毒性较小的邻位取代多氯联苯的快速光分解会优先产生毒性更大的共面…如果在阳光下发生类似的光解，则会产生更多的多氯联苯作为中间体，这可能会造成严重的环境问题。(2)在未混合的有机溶剂中，采用基于硅胶的各种电子给体和电子受体键合固定相，实现了标准品合成过程中产生的所有二恶英异构体的分离以及共面和邻位取代多氯联苯之间的基团分离。这使得有机溶剂在制备操作中易于回收。(3)以星爆树状大分子和聚烯丙胺为载体，通过烷基化和羧酸基团的连接制备了伪固定相。在水-甲醇或水-乙腈混合物中，EKC的伪固定相，特别是具有长烷基链的固定相，表现出非常高的性能，可以在不到20分钟的时间内完全分离16种优先污染的多核芳烃。结果表明，如果在阳光下进行类似的光分解，已经释放到环境中的多氯联苯的光解作用对生物物种具有潜在的非常危险，并且控制和适当处置剩余的多氯联苯非常重要。研究结果还表明，开发一种更具选择性、敏感性和快速的环境污染物分析方法对于生物样品的处理需要最少的人工是很重要的。少

The objectives of this project include (1) the development of a photolysis method of dioxins and PCBs in aqueous waste, (2) the development of a high selectivity separation method of dioxin isomers and PCB congeners by HPLC,and (3) the development of a novel pseudo-stationary phase for the high-speed and high-selectivity EKC separation of environmental contaminants, namely hydrophobic hydrocarbons and halogenated aromatic compounds.(1) PCBs were successfully adsorbed from aqueous solution onto the hydrophobic stationary phase packed in a quartz column, the photolyzed by the irradiation with ultra-violet light from outside the column. All the PCBs can be completely photolyzed in a few hours in a stream of 2-propanol-water mixtures, while only hydrophilic products leaving the column. The photolysis of more toxic, coplanar PCBs were slower than ortho-substituted PCBs. The rapid photo-decomposition of less toxic, ortho-substituted PCBs, however, preferentially produced more toxic coplanar … More PCBs as an intermediate, which can potentially provide serious environmental problems, if similar photolysis occurs under sunlight.(2) The separation of all the dioxin isomers coproduced during the synthesis of reference standard and the group separation between coplanar and ortho-substituted PCBs were achieved by using various electron-donor and electron-acceptor bonded stationary phases based on silica gel for HPLC in an unmixed organic solvent. This allows the easy recycle of the organic solvent in preparative operation.(3) Pseudo-stationary phases were prepared by using starburst dendrimers and polyallylamine as supports by alkylation and the attachment of carboxylate groups. The pseudo-stationary phases for EKC,especially those with long alkyl chains, showed very high performance in water-methanol or water-acetonitrile mixtures to result in the complete separation of 16 priority pollutant polynuclear aromatic hydrocarbons in less than 20 minutes.The results suggest that the photolysis of PCBs already released to the environment is potentially very dangerous to living species, assuming a similar photo-decomposition under sunlight, and that the control and proper disposal of remaining PCBs are very important. The results also suggest that it is important to develop a more selective, sensitive, and rapid analysis method of these environmental pollutants that needs minimum labor for the treatment of biological samples. Less