低浓度重金属废液的工业排放造成严重的资源浪费和环境污染，急需回收和治理，"十二五"规划把《重金属污染综合防治》提高到前所未有的高度。.针对液-液溶剂萃取、固-液固定床吸附分离技术在回收处理重金属离子废液过程中存在的问题，本项目将溶剂萃取和固定床两种分离模式的优点集成于一体，同时克服了两者各自的缺点，提出了一个全新的集成创新分离模式-磁性流体固定床萃取分离方法。.该方法利用高梯度磁性分离原理，将含萃取剂磁性流体以液滴的形式固定在分离柱金属丝表面，构建一个磁性流体液滴在分离柱内均匀分布、具有一定孔隙率的磁性流体固定床。它在形式上类似于固定床，但其"吸附剂"是被高梯度磁场控制的含萃取剂磁性流体液滴，而非固体颗粒，它的分离机理与液-液萃取相同。.在前期工作基础上，以重金属实际分离体系为对象，本项目拟系统开展磁性流体固定床萃取分离模式的理论分析和实验研究，为工业化处理解决关键科学问题和技术难题。

The low-concentration heavy metals discharged from industries are harmful to living species. Therefore, they must be removed from polluted streams in order to meet increasingly stringent environmental quality standards. However, there are some disadvantages for separating and recovering low-concentration heavy metals by conventional methods included solvent extraction and fixed-bed adsorption..The focus of this project is a novel, simple and rapid model of extraction process. The original so-called "magnetic-fluids fixed bed" (MFFB), which bridges solvent extraction and fixed-bed adsorption by the theory of the high gradient magnetic separation, has been explained. The MFFB integrates the advantages of the two above mentioned classical extraction methods and overcomes their drawbacks..In the high gradient magnetic separator filled with ferromagnetic steel wires, the magnetic fluids containing extractant are immobilized well-distributed as stationary phase in form of liquid-droplet on the surface of wires under nonhomogeneous magnetic field. The aqueous solution of heavy metal ions, as mobile phase, flow through controlled-porosity high gradient magnetic separator and is extracted by magnetic extractant. This method is similar to fixed-bed adsorption in form, but its extraction mechanism is solvent extraction because heavy metal ions are extracted by liquid magnetic fluids containing extractant..The Au(III) and Cr(VI) are selected as models of heavy metal ion in our research. The theoretical model of the extraction process is established, and the effects of various factors on the extraction efficiency of magnetic fluids containing extractant are investigated in details. The purpose of this project is to verify the feasibility of this method by the experiments and explore a new separation process to be suitable for extraction of low concentration heavy metal ions aqueous solution,.