ICP-OES determination of rare earth elements in silicate rocks using ultrasonic nebulization and on-line ion-exchange tron separation

Rare earth elements (REEs) were determined in geological samples by inducti vely coupled plasma optical emission spectrometry (ICP-OES) with online iro n separation using now injection (FI) with an ultrasonic nebulization syste m. The anion-exchange separation method of a hydrochloric system was applie d to the separation of REEs from iron. The iron-chlorocomplexes were retain ed on an anion-exchange (Dowex 1X-8) microcolumn (3.0 mm i.d. x 50.0 mm bed length), while the analytes were introduced into the ultrasonic nebulizati on system. After iron removal, a 700-muL sample was injected into a water c arrier stream. The sl:stem was found to have a detection limit of La 0.30 m ug/L; Ce 0.93 mug/L; Nd 0.51 mug/L; Sm 0.25 mug/L; Eu 0.045 mug/L; Gd 0.72 mug/L; Er 0.12 mug/L; Yb 0.01 mug/L; Lu 0.006 mug/L. The application of the method on Reference Materials GS-N (ANRT); AC-E (IGW), G-2, RGM-1, AGV-1 a nd SDC-1 (USGS) demonstrated that results were statistically indistinguisha ble from published values.