The Synthesis And Characterization Of Bisphenol A Molecular Imprinting Microsphere With Phenolic Resin

Bisphenol A is a kind of industrial raw materials, which is widely used in the preparation of PC and EPOXY. However, Bisphenol A is also typical Environment hormone. Environment hormone can influence human's function,even lead to canceration. Bisphenol A always enrichs in water environment and food cycle, traditional remove method difficultly carry out.Photodegradation and adsorption are the most useful method due to good good stability, non-pollution and high efficiency. Phenolic aldehyde microsphere has stable structure and large BET surface. The introduction of molecular imprinting technology can be benefit of improving the selectivity of microsphere, which has an important practical research significance. We use molecular imprinting technology in this paper. First, we prepare molecular imprinting organic microsphere (RF-MIP) and study its adsorption properties towards bisphenol A. Meanwhile, we prepare RF-MIP microsphere with different diameter and study its adsorption properties towards bisphenol A.Second, we prepare molecular imprinting organic-inorganic composite microsphere (Ti02@C-MIP) and study its degradation towards bisphenol A.At the same time, we study influence of microsphere photodegradation with different synthesis condition. The main research works are as follows:1. Preparing molecular imprinting organic microsphere (RF-MIP) by using one step sol-gel method, imprinted microsphere of phenolic aldehyde,template of BPA and solvent extraction method. The microsphere's morphology, thermal stability and so on were characterization by transmission electron microscope (TEM), thermogravimetric analyzer (TGA) and other measurement. RF-MIP had a particle size in the diamater of 450 nm, rough surface and good thermal stability. The adsorption properties of RF-MIP towards BPA was satisfactory, meanwhile the selective and competitive adsoption properties were also good The imprinted site on the RF-MIP surface had specific recognitive ability, good reproducibility. The adsorption process followed pseudo-second-order kinetics model and Freundlich isothermal adsorption model. RF-MIP was used to concentrated BPA as the enrichment material. The concentration of BPA could be measured via an chemometrics based total reflection infrared spectroscopy (ATR) method. Experimental results had a good linearship with predicted results, which could detect the minimum concentration of 10 mg/L. By changing proportion of ethyl alcohol and water, we also prepared RF-MIP microspheres with different diameters,their morphology and diameters were characterization by TEM and DLS.Those microspheres had an homogeneous diameters of 200 nm, 450 nm and 750 nm, respectively. After studying the adsorption properties towards BPA of those microspheres, the adsorption process followed pseudo-second-order kinetics model. The microsphere of smallest diameter had best adsorption ability and highest reproducibility.2. Preparing molecular imprinting organic-inorganic composite microsphere (TiO2@C-MIP) by using two step sol-gel method, template of BPA, Tetrabutyl orthotitanate as crosslinking agent and calcination to remove template. The microsphere's morphology, elementary composition, crystal property and so on were characterization by scanning electron microscope(SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and other measurement. TiO2@C-MIP had raspberry-like morphology and average diamater of 500 nm. TiO2 of anatase crystal phase distributed on the surface of microsphere. TiO2@C-MIP had large BET surface and good thermal stability.Ti02@C-MIP had specific binding site due to molecular imprinting technology, which would provide good adsorption properties, selectivity and competitiveness towards BPA. The adsorption process followed pseudo-second-order kinetics model and Freundlich isothermal adsorption model. TiO2@C-MIP also had selective photodegradation ability towards BPA,photodegradation rate reached to 94%. The repeated experiment demonstrated TiO2@C-MIP was renewable. In the end, we systematically studied the influence of microsphere and photodegradation properties of preparing Ti02@C-MIP, which involved initial addition, calcination temperature,template additive amount and reactive time. Ti02@C-MIP had best photodegradation ability towards BPA when initial addition enlarged 4 times,calcination temperature maintained 550 ?, the template and crosslinking agent had a ratio of 1:20, the reactive time was 14 h.