Preparation, Characterization And Application Of Molecularly Imprinted Polymers Toward Phenol And 2,4-Dichlorophenol

Efficient and rapid technologies for sample pretreatment in the analysis of low-level compounds have aroused increasingly interests. Molecular imprinting technique (MIT) is a kind of polymer synthesis method which has a predetermined recognition ability for target analytes. Target analytes could be enriched by the molecular imprinting technique coupled with solid phase extraction (MIP-SPE) from the complex system selectively. MIP-SPE method has many advantages, such as high specificity, high selectivity, good stability and so on. In recent years, MIP-SPE has become the most promising technologies in the field of analytical chemistry.In this thesis, the solid phase extraction column of phenol and 2,4-dichlorophenol was prepared, and we establish the detection methods of a low concentration phenolic compounds in wastewater. The main work of the thesis includes the following three parts:1,The molecularly imprinted polymers with phenol as the template molecule and 4-vinylpyridine (4-VP), ethylene glycol dimethacrylate (EDMA) as functional monomer and the cross-linker, respectively, has been prepared by bulk polymerization. Adsorption ability and selectivity of the polymer were estimated by saturation binding experiment and chromatographic method, respectively. It was demonstrated that phenol imprinted polymers had a certain adsorption capacity and selectivity for phenol relative to the blank imprinted polymers.2,The MIP-SPE in combination with HPLC method had been set up which was used to determine phenol and other phenolic compounds with phenol imprinted polymers as extraction materials. Washing solvent, elution solvent and pH value which affecting the extraction efficiency of the polymer have been optimized. When using 1.5 mL methanol (containing 60%, v/v, water) as washing solvent,3.5 mL acetonitrile (containing 1%, v/v, acetic acid) as eluent solvent, the highest extraction recovery of phenol was obtained. The average recoveries are 100.25%,91.30%and 88.39% (n= 3) for phenol,2-chlorophenol and 2,4-dichlorophenol under optimization conditions, respectively. The recovery reached to 88.22% (RSD= 1.2, n= 3) for phenol when the method was used to analyze phenol in the water sample under the optimum conditions and the linear range and detection limit for phenol were 0.05-10.00μg/mL and 0.002μg/mL, respectively.3,2,4-dichlorophenol molecularly imprinted polymers have been prepared by bulk polymerization. The adsorption capacity and selectivity of polymer toward the template molecule were assessed by the equilibrium binding experiments and chromatographic method. The method which 2,4-dichlorophenol molecularly imprinted solid-phase extraction combined with HPLC has been set up and was used to determine 2,4-dichlorophenol and other phenolic compounds. The recovery was 88.19% (RSD= 1.2, n= 3) for 2,4-dichlorophenol when the method was used to analyze water sample and the linear range and detection limit for 2,4-dichlorophenol were 0.08-10.00μg/mL and 0.020μg/mL, respectively.