Adsorption Behaviour of La(III) and Eu(III) Ions from Aqueous Solutions by Hydroxyapatite: Kinetic, Isotherm, and Thermodynamic Studies
Table 1
Kinetics models applied to experimental data and parameters evaluated for [La(III)] = 5.7 10−5 M and [Eu(III)] = 6.5 10−5 M adsorption on hydroxyapatite at room temperature and pHeq = 5.75 ± 0.03.
Models, equations, and [conditions]
Parameters
La(III)
Eu(III)
Pseudo-second-order
(g/mg minute) (mg/g)
8.5 0.25
0.65 0.98
Intraparticle mass transfert diffusion
[t = 0 to 1 minute]
(mg/g minute1/2)
0.04
0.22
[La(III): t = 1 to 7 minutes] [Eu(III): t = 1 to 15 minutes]
(mg/g minute1/2) C (mg/g)
5.5 10−4 0.17
0.026 0.32
[La(III): t = 1 to 7 minutes] [Eu(III): t = 15 to 60 minutes]
