| In the thesis, a new polyamine-type/carboxyl-containing amphoteric ion exchange fiber(IEF) based on polyacrylonitrile (PAN) with higher exchange capacities was prepared by crosslinking through hydrazine hydrate, followed reacting with diethylene triamine. The influences of fiber diameter, reaction time and temperature on the reaction were studied. The structures of the IEF were characterized by the means of IR spectrum, EA and SEM and the mechanism of the synthesis reaction was investigated.An anion exchange fiber was prepared based on synthesized IEF by chelating with ferric chloride solution, which was used to adsorb fluoride and iodide ions from aqueous solutions and the influences of various kinds of conditions on adsorption capacity were discussed. The results showed that the fibrous sorbent has high adsorption capacity and quick kinetic property for fluoride ion and iodide ion. The adsorption kinetic process can be described by Lagergren pseudo-second-order equation, and Freundlich model can simulate the adsorption equilibrium in the studied concentration range. The maximum adsorption capacities for fluoride ion and iodide ion were 30.2mg/g and 321.2mg/g, respectively. The activation energy of adsorption to fluoride ion was largely influenced by temperature and it benefited to adsorb fluoride ion in above 27℃. Fluoride ion and iodide ion adsorbed on the PAN fiber could be desorbed by Al(NO3)3 and NaOH. And this process showed the fiber was easy to desorb and can be used repeatedly.It could be concluded that Ag+ was the most effectively adsorbed on the polyamine-type/carboxyl-containing IEF based on polyacrylonitrile at static and dynamic experiments when Cu2+, Pb2+, Cd2+, Ag+, Zn2+, Co2+ ions coexisted. Besides, the influences of pH value, the weight increase of fiber and original concentration of Ag+ on the adsorption were studied, and the preliminary discussion on adsorption mechanism was also given in this paper by comparing with the IR spectrum.
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