Preparation And Adsorption Characteristics Of The Lead(Ⅱ) And Cadmium(Ⅱ) Ion Imprinted Polymers

Two novel type ion imprinted polymers were prepared by molecular imprinting technology. The ion imprinted polymers were prepared by bulk polymerization using lead(II) ion and as cadmium(II) ion templates. Environmental scanning election microscope (ESEM) was used to analyze properties of the products. The adsorption properties and imprinting efficiency of IIPs were studied through batch tests with ultraviolet spectrum,infrared spectrum. The main results of the studies as follows:1. A brief overview is given for the profile and the methods of separation and preconcentration of Pb(II) and Cd(II), the principle of molecular imprinting technology, the preparation of molecular imprinted polymers, and the application in the metal separation and enrichment of molecular imprinted polymers.2. The ion imprinted polymer was prepared by bulk polymerization using lead(II) ion as a template, salicylaldoxime and methacrylic acid as functional monomers and ethylene glycol dimethacrylate (EGDMA) as a crosslinker. The presence of interaction between template and monomer was proved by the change of UV spectrum. The preparation of IIPs was successful by IR spectroscopy. The adsorption properties and imprinting efficiency of ion imprinted polymer were studied through batch tests with ultraviolet spectrum,infrared spectrum. The results obtained show that, in comparison with non-imprinted polymers, the sorption equilibrium was achieved in 40 min and the maximum sorption of lead(II) imprinted polymers was about 949μg/g by Pb2+ was 10 mg/L. The maximum static adsorption capacity of the IIPs was 22.53 mg/g. The best acidity was pH=3. Experimental results show that the adsorption of IIPs fits the Lagergren's first-order rate equation. Thermodynamics show adsorption processes is heat-sink spontaneous process, The static adsorption modulus was 132.6μg/mL and separate factor was 9.6. 3. The ion imprinted polymers was prepared by bulk polymerization using Cd(II) ion as a template,α-benzoinoxime and methacrylic acid as functional monomers and ethylene glycol dimethacrylate (EGDMA) as a crosslinker. The presence of interaction between template and monomer was proved by the change of UV spectrum, and the best ratio is 1:2. The polymerization between Cd(II) and benzoin oxime was complete, the characteristic peaks of functional groups did not change significantly. Environmental scanning election microscope (ESEM) was used to analyze properties of the products. The adsorption properties and imprinting efficiency of IIPs were studied through batch tests with ultraviolet spectrum,infrared spectrum. The results obtained show that, in comparison with non-imprinted polymers, the sorption equilibrium was achieved in 50 min and the maximum sorption of Cd(II) imprinted polymers was about 2.12 mg/g. The maximum static adsorption capacity of the IIPs was 31.76 mg/g. The best acidity was pH=5. Experimental results show that the adsorption of IIPs fits the Lagergren's first-order rate equation.The static adsorption modulus was 383.5μg/mL and separate factor was 9.7.