ADSORPTION OF OXOVANADIUM(IV) FROM AQUEOUS SOLUTIONS BY NANOPARTICULATED HYDROXYAPATITE. THERMODYNAMIC AND KINETIC STUDY

ENRIQUE D. VEGA; JOSÉ C. PEDREGOSA; GRISELDA E. NARDA

Journal of the Argentine Chemical Society

ASOCIACIÓN QUÝMICA ARGENTINA

Lugar: Buenos Aires; Año: 2009 vol. 97 p. 1 - 12

0365-0375

This work reports some interesting thermodynamic and kinetic data dealing with the interaction of oxovanadium (IV) ions with synthetic calcium hydroxyapatite. Their uptake, or ion exchange adsorption, was investigated at different temperatures (range from 288 to 308 K). The amount of the uptake, measured by atomic absorption spectrometry, shows that oxovanadium(IV) ions are adsorbed on the surface of hydroxyapatite by coordination to OH groups. The adsorption is dependent upon pH and temperature, the maximum adsorption being at pH 3.5 and 288 K. The proposed adsorption model is coherent with the experimental data. All the thermodynamic and kinetic parameters were in concordance with the proposed adsorption reaction.