Extraction of lanthanides ions (III) from aqueous solution by sodium salt of the N(4-amino-benzoate)-propyl-silica gel

The silica gel 60 of specific superficial area 486 m2.g-1 was modified chemically with the ligand 4-amino benzoate of sodium in water-ethanol environment (l:L). The adsorptions of metallic ions were from water solutions at approximately 2 x 10-3 M of chloride of Pr(III), Nd(III), Eu(III) and Ho(III). In these experiments we could see that the system gets the equilibrium of adsorption rapidly and that the pH of the environment has a great influence on the process of adsorption, being that the number of metal mols adsorpted in the matrix varied between 10,00 and 17,00 x 10-5 mols. g-1 with a pH of approximately 5 for all the lanthanides, where the adsorption curves reach equilibrium. (author)