Study On The Preparation And Properties Of Molecular Imprinted Polymer For Methylene Blue And Cr(?)

The new molecular imprinted polymers(MB-MIP and Cr(?)-MIP) were prepared with Cr(?) and Methylene blue(MB) as the imprinted template molecules, acrylic acid(AA) as the functional monomer, N,N'- methylene bisacrylamide(MBA) as the crosslinker, 2,2'-azobis(2-methylpropionitrile)(AIBN) as the initiator. They were synthesized by bulk polymerization and inverse microemulsion polymerization, respectively. The structure and morphology of MIPs were characterized by SEM, BET and FTIR spectra, and the effect of pH, reusability and swelling ratio of MIPs were studied. Through comparing simulation analysis with experiments, the maximum adsorption amount, selective adsorption, kinetics, adsorption isothermal and thermodynamics of MIPs were systematically investigated.It was found that the adsorption capacity of the MIPs were much higher than the NIP,and its value increases with the increase of initial concentration of imprinted template molecules Simultaneously. The maximum adsorption amount of the Cr(?)-MIP and the MB-MIP were 69.49 mg g-1 and 3628.84 mg g-1, respectively. The result of Scatchard analysis of MIPs showed that there are two different binding sites: higher binding sites and lower binding sites. The competitive anions were employed for specificity adsorption test, demonstrating that the MIPs were the highest specifical rebinding to the imprinted template molecules. In addition, the adsorption property of the MIPs were well represented by the Langmuir isotherm model and the pseudo-second-order model kinetic model. The study on thermodynamic parameters suggested that the adsorption process was spontaneous, endothermic with dominating by entropy.