Study On Design, Preparation And Properties Of Novel Adsorption Functionallizing Materials

This thesis reviewed the domestic and international research progress of adsorption and separation functional polymer materials in detail. On that basis, three kinds of novel adsorbents for heavy metals were designed and prepared. The novel adsorbents obtained in this thesis were characterized and their adsorption properties for metals were also investigated. The dissertation results are as follows:1. Design and synthesis of chelating resin with cyanoguanidine moiety (PS-DCDA). A novel chelating resin containing cyanoguanidine moiety has been successfully prepared by the functionalizing reaction of a macroporous bead based on chloromethylated copolymer of styrene-divinylbenzene with dicyandiamide. The adsorption properties of the resin for Hg(II) were investigated by batch and column methods. The results indicated that the resin displayed a marked advantage in Hg(II) binding capacity, and the saturated adsorption capacity estimated from the Langmuir model was dramatically up to1077mgg-1at45℃. Furthermore, it was found that the resin was able to selectively separate Hg(II) from multicomponent solutions with Zn(II), Cu(II), Pb(II) and Mg(II). The desorption process of Hg(II) was tested with different eluents and the ratio of the highest recovery reached to96%under eluting condition of1M HC1+10%thiourea.2. Design and synthesis of chelating resin with amidoxime group(PSGA). A novel chelating resin containing amidoxime functional group has been synthesized by reacting PS-DCDA with hydroxylamine. Batch method was applied for testing the adsorption behavior of the resin for Ag(Ⅰ) in aqueous solution. It is noteworthy that, PSGA has high adsorption capacity and good selectivity towards Ag(Ⅰ), which can be easily desorbed after adsorption.3. Design and synthesis of polysulfone capsules containing ZrP (PSF@ZrP capsules). Zirconium phosphate (ZrP) was immobilized by microencapsulation process of polysulfone (PSF) to form the polysulfone capsules containing ZrP (PSF@ZrP capsules) successfully by using phase inversion precipitation technique, and the PSF@ZrP was employed as capsules adsorbents to remove Pb2+presented in aqueous solution. The result shows that an encapsulation capacity of50%(mass ratio, PSF:ZrP=1:1) should be the optimal proportion of ZrP encapsulated with PSF. It was found that the adsorption of the PSF@ZrP capsules for Pb2+would be pH dependent due to the ion-exchange mechanism, and the uptake of Pb2+was slightly influenced with the concentration of coexisting cations (Na+, K+) in a low range. Furthermore, the calculated thermodynamics parameters exhibit that the nature of the adsorption process is spontaneous and exothermic. After six times of adsorption-regeneration cycles, no significant loss of adsorption capacity was observed, indicating the good stability of the PSF@ZrP capsules.