Sorption of rare-earth erbium from aqueous solution onto sol-gel-derived zirconia

Abstract

Zirconia powder was synthesized via sol gel method and used for erbium sorption. The adsorption is strongly dependent on pH of the medium where the removal efficiency increases as the pH turns to alkaline range. The process was very fast initially and maximum adsorption was attained within 60 min of contact. Pseudo-second-order model and homogeneous particle diffusion model (HPDM) was found to be the best to correlate the diffusion of erbium into zirconia particles. Adsorption thermodynamic parameters were calculated. Erbium adsorption is an endothermic (ΔH > 0) and good affinity of erbium ions towards the zirconia (ΔS > 0).

A spectroscopic study of trivalent cation (Cm3+ and Eu3+) sorption on monoclinic zirconia (ZrO2)

“…Eu 3+ was retained by both minerals in the mildly acidic pH-range (from pH 4 -5.5) and above, indicating an excellent retention potential of the material toward trivalent contaminants. A similar conclusion was reached by Salem and Yakout [82] investigating Er 3+ removal by sol-gel-derived zirconia, where the endothermic sorption reaction reached maximum Er 3+ uptake at pH > 5 under the given experimental conditions.…”