| Chlorinated phenolic, which is of great harm to the environment and organism, is difficult to be biodegradation and chemical degradation. Physical method, especially, the adsorption method is a good way to remove the chlorinated phenolic from environmental sample. But there are also some deficiencies for this method:firstly, most of the adsorbents don't have selectivity; secondly, it is difficult for the adsorbents to be separated from the sample matrix; at the same time, the regeneration process always complex and will waste lots of solution. Therefore, it is urgent to find a multifunction material that can solve these problems.In order to solve the problems mentioned above, this study combines magnetic separation, photo-catalytic regeneration, molecularly imprinting technology as a whole, targeted to develop a multifunctional and new-type material to remove the persistent organic pollutants,2,4DCP. The synthesized magnetic molecularly imprinted materials can selectively adsorb trace contaminants in water, also can be separated and reused easily. The characterization of MIPs was carried out by TEM, SEM, FT-IR, XRD, VSM, TGA. And a comprehensive study was underway of the adsorption and regeneration of the materials.(1) First, Fe3O4 magnetic core was prepared by chemical precipitation, and then used gol-gel method to coat a TiO2 layer, in combination with precipitation polymerization, finally the composite with imprinted polymer using 2,4DCP as template was prepared. The Soxhlet extraction was used to elute the template from the polymer to form MIPs. When we chose 4VP as function monomer, thermal initiation as the initial method (60℃), and the additive of inorganic consistent was 0.5g, the obtained materiasl owned the best absorbed removal efficiency. TEM, SEM, and FI-IR results showed that the obtained polymeric materials had an appearance of sphere-like aggregates with shell/core structure, and there were open pore space. VSM and XRD measurements showed that the introduction of MIP layer and TiO2 layer on the magnetic core didn't affect magnetic property. Magnetic MIPs had a high selective adsorption ability toward chlorophenol. The static adsorption fit the Langmuir adsorption isotherm, the maximum adsorption could reach 95.23mg/g, the imprinted factor was 2.98, and the adsorbed process corresponded dynamic process. Magnetic MIPs regeneration tests confirmed that synthetic materials can be reused several times by UV irradiation, and the regeneration rate could be maintain over 50% at least. (2) To improve the photo-catalytic regeneration performance, the obtained polymer above had been coated with a layer of porous TiO2 which added some metal cerium to improve the catalytic property. CaCO3 was chosen as the porogen to prepare the porous TiO2 photo-catalytic materials. The adsorption property of pure porous TiO2 was perfect, it could achieve equilibrium in a short time, and the photo-catalytic degradation rate nearly reached 100%. At the same tine, the adsorption capacity of the magnetic MIPs did not decline, when a porous TiO2 photo-catalytic layer covered on the surface. In addition, the photo-catalytic regeneration performance of the final materials was greatly improved, up to 70%.
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