| Ion exchange fiber (IEF) is a kind of novel functional material for adsorption and separation. Owing to its big effective surface area and short transit distance, it possesses many merits such as the high speed of adsorption and elution, fine regenerability, lower energy consumption and lower resistance etc. IEF can be used in the form of fiber, knit goods, unwoven cloth etc. Many new technology processes have been developed from these materials and have been widely used in individual breathing mask, air purification, environment conservation, bioengineering and hydra-metallurgy.In this thesis a new ion exchange fiber with higher exchange capacities up to 6.5mmol/g and good physico-mechanical properties was prepared by alkaline hydrolysis of PAN fibers crosslinked with aq-hydrazine. The influence of material ratio and temperature on reaction and the possible mechanisms of crosslinking and hydrolysis reactions were studied with IR , EA and other means. The physical and chemical properties were also characterized with thermal analysis and SEM means. The PH titration curve and swelling rate, mechanical properties, regenerability and chemistry stability were determined. The dynamic adsorption properties of the prepared function fiber for NH3, SO2, HC1, HF were studied and the effect of water content and diameter of fiber were determined. The results showed that the adsorption capacities of the fiber for NH3 and 862 were up to 56.2mg/g and 200mg/g respectively, but they were deeply affected by water content and diameter of fiber. The adsorption properties of the function fiber in solution for transition metal ion such as Zn2+,Cd2+,Hg2+etc., were studied and the effects of temperature, concentration, pHon adsorption were also determined. The results showed that the fiber exhibited fairly good adsorption properties, and the adsorption capacities for Zn2+.Cd2+,Hg2+ were up to 196.79mg/g, 275.40mg/g and 6,84.01mg/g respectively.
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