| Cyclodextrin (CD) polymers contain many satisfactory properties, not only the supramolecular performance of CD precursor, but also their stability, chemical tunability, and environmental compatibility. The CD polymers were mainly used to build chromatography chiral stationary phase, the skeleton of drug delivery and environmental protection, etc. Three β-CD polymers were synthesized and their adsorption performances(Qe) for basic fuchsin (BF) and methylene blue (MB) in water were studied in this dissertation.1.The crosslinked β-cyclodextrin polymer(PCD) was synthesized by cross-linking β-CD with crosslinker ethanediamine maleamic acid. The yield of PCD was25%and the β-CD content was29.9%by1H NMR, and its structure was confirmed by1H NMR, IR, SEM and TG.2. The influences of adsorption conditions such as the initial concentration (Co), system pH, time and temperature on the performance (Qe:adsorption capacity) of PCD adsorbing BF and MB were studied. The results showed that the Qe of PCD adsorbing BF and MB increased with the increase of Co, within the range of15～35℃; the Qe of PCD increases with increasing pH when the solution pH is2to7, and when the solution pH value is greater than7, the Qe of PCD basically keeps constant. When the tempreture was35℃, solid-liquid ratio was3.3g·L-1, and the adsorption time was2h, the maximum adsorption capacity of PCD adsorbing BF and MB are31.5mg·g-1and27.6mg·g-1, respectively. The adsorption isotherm and adsorption kinetics model were studied. The adsorption isotherm data of PCD adsorbing dye fit the Langmuir isotherm model in the range of10℃to35℃, thermodynamic constants of the adsorption process including△Gθ,△Hθ and△Sθ were calculated. Results showed that the process of PCD adsobing dye is spontaneous, and mainly physical adsorption. The adsorption kinetics data was consistent with the pseudo second-order kinetics model.3. Chloro-acetyl-β-CD immobilization polymer (PSMACD) was synthesized via two steps, firstly, the reaction of β-CD with styrene-maleic anhydride alternately copolymer (SMA) on the skeleton, and then chloroacetyl chloride, and its β-CD content was48.63%. The structure, morphology and thermal stability of polymer were characterized by IR, solid state13C NMR, SEM, TG.4. This paper was made the preliminary study to adsorption isotherm model and the kinetic model of PSMACD adsorbing BF and MB. The adsorption of PSMACD for BF and MB fit Langmuir adsorption isotherm model and was monolayer adsorption; the adsorption kinetics data was in accordance with the pseudo second-order kinetic model. When the tempreture was35℃, solid-liquid ratio was0.25g·L-1, and the adsorption time was12h, the maximum adsorption capacity of PSMACD adsorbing BF and MB which was calculated by the Langmuir adsorption isotherm model were335.57mg·g-1and657.89mg·g-1, respectively.5. Crosslinked and immobilized polymers were prepared by β-CD-calix[4]arene derivatives(β-CD-CA), the structure of polymers were confirmed by IR, solid state13C NMR, SEM and TG. Adsorption performances of polymers for BF were made a preliminary study. The results showed that using the hexamethylene isocyanate (HMDI) as crosslinker, the adsorption properties of the crosslinked polymer were preferable when the molar ratio (HMDI:β-CD-CA) was2:1. When the tempreture was25℃, solid-liquid ratio was3.3g·L-1,and the adsorption time was2h, Co was21mg·L-1, the adsorption rate (E) is93.5%, and the maximum adsorption capacity is12mg·g-1When the molar ratio (β-CD-CA:SMA) was1:5, the immobilization polymer showed a satisfied adsoption performance. When the tempreture was35℃, solid-liquid ratio was0.25g·L-1, and the adsorption time was12h, the adsorption capacity can reach224mg·g-1. |
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