Sorption and desorption of Fe(III) on natural and chemically modified zeolite

The Fe(III) uptake from aqueous solutions by natural and chemically modifie d zeolites was investigated using a gradual radioexchange method and AAS te chnique. The leachability of Fe(III) from loaded zeolites was studied too. The Fe-uptake reached the value of 60 mg.g(-1) for the zeolite chemically t reated with 6 mol.l(-1) solution of NaOH and it is more than twelve times h igher than that of the raw zeolite. The leachability of the loaded zeolite samples in water and alkaline-solution was up 5%. The leachability of the s ame zeolites in acid solution depended on the concentration of modifying so lution. The leachability at pH = 2.6 in the range 2-20% at pH = 1.9 was man y times higher. The results of the radioexchange and AAS methods were compa red.