Abstract

A new method using a micro-column packed with nanometer sized TiO₂ as a sorbent has been developed for the on-line preconcentration of trace amounts of rare earth elements (La, Y, Yb, Eu and Dy) prior to their determination by inductively coupled plasma atomic emission spectrometry (ICP-AES). The effects of pH, sample flow rate and volume, elution solution and interfering ions on the separation of analytes have been investigated. The adsorption capacity of nanometer TiO₂ for La, Y, Yb, Eu and Dy was found to be 7.0, 6.1, 9.8, 8.3 and 8.8 mg g⁻¹, respectively. The method has been successfully applied for the determination of trace rare earth elements in some environmental samples.