| Polymer adsorbent material is usually known to have specific molecules or ions and possess specific affinity function. It can be applied to liquid and gas phase adsorption and then gradually substitute the traditional inorganic adsorbents due to its larger pore size and specific surface area. Accompanied with the high-speed economic development of science and technology level, the synthetic polymer adsorbent material is also following the rapid step of development. Some novel adsorbent materials such as molecularly imprinted materials with specific recognition capabilities and adsorption-type materials having micro/nano-porous structure spring up like mushrooms, which are widely used in industrial wastewater treatment, medicine and health chemical engineering and agriculture, etc. It can overcome the defects of traditional adsorbent materials such as the low adsorption capacity poor regeneration as well as the low selectivity of minerals, activated carbon and adsorptive resin. Hence, studying the preparation of such new adsorbent materials possess marked social value and practical significance. Pickering high internal phase emulsion polymerization is an effective method for preparing porous polymer materials utilizing the solid particles as emulsifier in emulsion polymerization. The structural morphology and physical properties of porous materials can be readily controlled via adjusting the type and concentration of surfactant, the volume fraction of the dispersed phase or two-phase composition, etc. Above all, porous adsorbent material prepared by Pickering high internal phase emulsion template is of precious application value.Magnetic composite materials are composited materials with magnetism and special structure, which combine organic polymers with inorganic magnetic materials by a proper approach. It could have superparamagnetism through the copolymerization and surface modification that endow with the reactive functional groups on the surface. It can be convenience to locate and separate under the external magnetic circumstance.Molecularly imprinted polymers have a specific recognition for the target molecular for the adsorption and separation. It can overcome the traditional adsorption disadvantages, in which the capability of adsorption is low and has the poor selectivity. Also, it can resist high temperature, high pressure, acid and alkali, organic solvents and so on with the well chemical and physical stability. Therefore, it is easy to prepare and store to realize industrialized production. Molecularly imprinted polymers as a promising specific adsorption material is gradually mature which significant attention has been paid.In the article, it is synthesized porous and magnetic imprinted adsorption material by the polymerization, the preparation of magnetic material and the molecular technology, respectively. It is researched for antibiotics and pesticide pollution of its application in the adsorption behavior. The UV visible spectroscopy (UV), infrared spectroscopy (FTIR), thermal gravimetric analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), magnetic (VSM), contact angle analysis and other means were used to visualize the adsorption material surface morphology, structure, and surface wettability of characterization conducting the further analysis. Batch static adsorption experiments systematic perform several kinds of selective adsorbent with separation from some typical pollutants behavior, which clarify the properties of the equilibrium and kinetic adsorption separation process and so on. It has carried on the application of the practical sample.1. Preparation and performance study of porous composite materials based on Picking high internal phase emulsion polymerization(1) Macroporous polymers foams (MPFs) were prepared by W/O Pickering high internal phase emulsions (HIPEs) stabilized by oleic acid (OA) modified silica nanoparticles (SPs), and then as-prepared MPFs were applied to highly efficient adsorption of 2,4,5-trichlorophenol (TCP). The FTIR, SEM, TEM, TGA and contact Angle tests were carried out to characterize the morphology and structure of MPFs. The characterization demonstrated that MPFs possessed macropore (50-150 μm) and interconnected pores (0.5-2 μm), and also had slightly hydrophobic nature (contact angle was 116°) and excellent thermal stability especially bellow 200℃. In static dynamic experiments, the maximum adsorption capacity and equilibrium time at 25℃ were 167.7 mg g-1 and 30min at optimized pH=6.0. Moreover, the experimental data indicate that equilibrium isotherms for TCP fitted to the non-linear Langmuir model and both the adsorption and desorption kinetics can be represented by the pseudo-second-order model. Thermodynamic parameters show that the MPFs adsorption of TCP is a spontaneous endothermic process. In addition, the regeneration of the MPFs has good performance.(2)Two kinds of macroporous polymer foams (MPFs1 and MPFs2) were prepared through O/W Pickering high internal phase emulsions (HIPEs) stabilized by the natural clay Halloysite Nano-Tubes (HNTs) nanoparticles with adding small amounts of nonionic surfactant Tween85 and used for adsorbing pyrethroids. The resulting MPFs were characterized by FTIR, SEM, TGA and static water contact angle, and the results showed the open cell structure with interconnected pores and hydrophilic surface with suspended state in aqueous solution. The findings of kinetic and equilibrium studies revealed the pseudo-second order kinetic model and the Langmuir isotherm were the best fitted models (R2>0.99) implying that the process of adsorption is monolayer and chemical reactive, respectively. In addition, the equilibrium adsorption capacity of MPFsl was’ greater than that of MPFs2, which could also due to the interconnected pores.2. Preparation and performance study of molecularly imprinted materials with su perparamagnetic susceptibility base on precipitation polymerization(1) A general and effective method for preparing molecularly a imprinted polymer nanoshell on magnetic halloysite nanotubes (MHNTs) to make highly-controllable core-shell nanorod (MMINs) is described for the first time, and the as-obtained nanomaterials were then used for selective recognition and rapid adsorption of tetracycline (TC) from aqueous solution. Use a variety of characterization methods to study the structure and morphology characteristics of MMINs. The MMINs with a shell controlled thickness exhibited the largest saturation adsorption capacity to TC, and the equilibrium data was well-described using the Langmuir isotherm model. The kinetic experiment showed a pseudo-second-order kinetic model was used to fit the data well. The nanocomposites displayed selective recognition for TC and could be rapidly separated from solution by a magnet, with good stability and regeneration property.(2) Mesoporous silicananoparticles (MSN) were prepared by a soft-template method. Magneticmesoporous silica nanoparticles (MMSN) were obtained by thermally reduction of the iron salt by ethylene glycol at hightemperature in the pore, which was introduced by the impregnation method. Thepolymerable functional groups were grafted into the surface of MMSN via silylationreaction. Acetonitrilewas used as solvent, chloramphenicol as template molecule, MMA as functionalmonomer, EGDMA as cross-linked agent, respectively, and surface imprintedpolymer based onto MMSN was prepared by in-situ precipitation polymerization(MMSN@MIPs). The structure and morphology of MMSN@MIPs was characterized byvarious methods, such as SEM、TEM、VSM、XRD、BET、TGA and FT-IR.The isothermal adsorption, kinetics, selectivity and regeneration ability ofMMSN@MIPs toward CAP was investigated through batch adsorption experiments. Theisothermal adsorption model showed Freundlich isothermal equation fitted the experimentaldata better, indicating that the adsorption process is dominated by multimolecular layer adsorption. The kinetics data was better fitted to the pseudo-second-orderkinetic model. The selective adsorption experiment exhibited that MMSN@MIPs hadgood selective recognition to CAP.3. Preparation and performance study of molecularly imprinted materials with su perparamagnetic susceptibility base on atom transfer radical polymerization(1) The Fe3O4 nanoparticles were modified by KH-570 and used as magnetically susceptible copolymer monomer with function monomer methacrylic acid (MAA) and templates TC, cross-linker ethylene glycol dimethacrylate (EGDMA) and initiator system were added into the solution which was contained surfactant to prepare the TC magnetic MIPs nanoparticles (MMINs) under the technique ATRP. The structure, morphology and magnetic of the MMINs were studied by FTIR、SEM、TEM、TGA and VSM; the results of the batch rebinding studies reflected that the adsorption of TC obeyed pseudo-second-order rate equation well and may be the rate-limiting step that controlled the adsorption process for TC and the absorption isotherm accorded with Langmuir model. It was reflected from the selectivity studies that the MMINS has specific selectivity to the TC. It was reflected from the comparison of TC-MIPs with existing reports that MMINs based on the ATPEP had higher selectivity and adsorption. In the end, solid phase extraction to the TC in the pork was examined and detected the TC in the pork by HPLC recovery of standard addition method.(2) It is calcinated to produce magnetic halloysite nanotubes (MHNTs) with a high temperature, ethylene glycol as the reducing agent, the halloysite impregnate iron nitrate. On the surface of the magnetic halloysite, it is modified by amino and grafted the active initiator through the amidation reaction.The sulfamethazine (SMZ) as the template molecular, it is utilizing the surface initiated atom transfer radical polymerization to prepare the magnetic halloysite surface imprinted composite nano materials (MNIMs), which graft hydrophilic polymer brush in molecularly imprinted polymer with the atom transfer radical polymerization of the secondary surface caused. All the studied on the structure,magnetic properties of MMINs and the magnetic properties by FTIR, SEM, TEM, TGA and the hysteresis loops and so on. The results showed HMMINs has better thermal and chemical stability that the polymer brushes were only 12 nm and 3.5 nm.With the multi molecular layer adsorption, the adsorption isotherm data were better fitted by the Freundlich isotherm equation. The HMMINs exhibits excellent adsorption selectivity and good regeneration performance for the template. It is because of not only the polymerization of ultra-thin layer and the SMZ of adsorption reached equilibrium within 1 h, but also the experimental data conformed to the pseudo-two-order kinetics model. |
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