DCP-ATOMIC EMISSION SPECTROMETRIC STUDY OF REE IN PHOSPHATES

A method has been developed for the application of direct current plasma atomic emission spectrometry (DCP-AES) to the determination or rare earth elements (REE) in samples of phosphates collected from the Abu Tartur area, Western Desert, Egypt. Complete dissolution of the samples was achieved using an HF/HNO3/HClO4 digestion procedure. Careful study of line overlap interference originating from REE as well as from minor and major constituents of the samples enabled the selection of the RE spectral lines appropriate for the analysis. Optimization of the DCP was necessary with respect to gas pressure and observation zone. The matrix effect due to the presence of Ca and Al was studied. The total content of REE directly determined in the samples ranged between 1.054 and 1.648 mg/gm. The. results reveal the applicability of the DCP-AES for the direct determination of 11 REE in phosphate samples.