Preparation And Application Of Pan-Based Amphoteric Ion Exchange Fiber

In order to develop PAN-based ion exchange fiber to enhance the usefulness of ion exchange fiber,PAN fiber was used as substrate in this study.Weak acidic and weak basic amphoteric ion exchange fibers of different exchange capacity were prepared from PAN fiber by means of chemical modification,copolymerization,chloromethylation and amination.Through the exploration of various process parameters of the study,the optimum synthesis condition was obtained. IR spectrum and SEM were used to characterize structure of the ion exchange fibers,whose physical and chemical properties were also characterized with thermal analysis.The results showed that weak acidic exchange capacity of the fiber was 2.53mmol/g and weak basic exchange capacity of the fiber was 1.77mmol/g,the exchange capacity was higher and the mechanical capability was finer.The method in preparation of weak acidic and weak basic amphoteric fibers from PAN fiber was feasible.Fluoride,silver and calcium ions adsorption conditions of the fiber from aqueous solution were stuied,the influences of different pH conditions and concentrations on the adsorption properties of the fiber were discussed.The results showed that the fibrous sorbent had high adsorption capacity and quick kinetic property for fluoride ion and silver ion and calcium 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 adsorption capacities for fluoride ion and iodide ion were 1.36mmol/g,0.88mmol/g and 0.89mmol/g,respectively.Measured the performance of fiber regeneration and this process showed the fiber was easy to regenerate and can be used repeatedly.