Analysis of Metallic Elements in Refractory Tantalum-Niobium Slag by ICP-AES

A new method for analysing the contents of many metalic elements, such as Ta, Nb, Sn, Ti, W, Fe, Mn, Al, Ph, Ce, Y, Sc, Pr, Sm, Nd, U, Th etc, in refractory tantalum-niobium slag by ICP-AES was developed. The samples processing procedures involve two steps, being first decomposed by potassium carbonate and boric acid at 950 degrees C for 15min, then leached by hydrochloride and tartaric acid at 90 degrees C for 30 min. The interference of flux and tin matrix in analyzing the other elements was eliminated by the utilization of matrix matching method. This method showed satisfactory precision and accuracy with the RSDs between 0.27% and 5.48% and the recovery rates between 94.0% and 109.6%. The analysis results indicated that highly valuable metals of Sn, Ta, Nb, Ti, W and Ce are rich in the refractory tantalum-niobium slag, showing that it has the great potential for comprehensive utilization. However, the analysis result also showed that the slag is a radioactive pollution source due to a small amount of U and Th. This method is simple and fast, and has the advantage of analyzing many elements simultaneously. The accurate analytic results provided a basis for the future researches on the comprehensive utilization of refractory tantalum-niobium slag.