| Fe-activated clinoptilolites were used to improve fluoride adsorption capacity of material in this paper. And Fe-activated clinoptilolites were prepared by two methods of static and dynamic impregnating with 5%FeCl3 solution after with 2%NaOH solution. Physiochemical properties of Fe-activated clinoptilolites, 2%NaOH pretreatment clinoptilolite and raw material were characterized by means of chemical analysis, XRD, FT-IR, TG-DTA, specificsurface and pore structure spectroscopy. The results indicates that their crystal structures and thermostability have no obvious change, but content of Fe have rather obvious improve in Fe-activated samples. After treatment of FeCl3 solution, specific surface area and pore volume have sharply enhanced. Dynamic impregnating is beneficial to enlarging specific surface area and pore volume.Properties and mechanism of fluoride adsorption were concerned. Adsorptions had been modeled by Langmuir, Frendlich, D.R. isotherm. Adsorption system involving clinoptilolite static impregnated with FeCl3 solution follows these equations but sample prepared by dynamic impregnating is not fit well. Free energyof adsorption (E) is caculated. The adsorption form of the former system is determined as chemical type, and the latter system involves both physical and chemical adsorption. These results are on the basis of value of free energy of adsorption, physiochemical characterization analysis and adsorption property study. Dynamic and thermomechanical study was carried out, including calculating some dynamic parameters and thermomechanical functions .Additionally, some practical applying experiments such as municipal high-fluoride-content drinking water treatment and regeneration of materials had been done, and showing practical value of this work.
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