Inductively coupled plasma atomic emission spectrometric determination of niobium and tantalum in ore sample after microwave digestion

The ore sample was digested with hydrofluoric acid by microwave heating,and then treated with tartaric acid solution to make niobium and tantalum in ore sample completely dissolve in solution.The niobium and tantalum in the prepared solution were determined by inductively coupled plasma atomic emission spectrometry(ICP-AES) under the selected instrumental parameters using Nb 316.340{106} nm and Ta 268.517{125} nm as analytical lines.The emission spectral intensity of niobium and tantalum showed good linear relationship with ρ(Nb2O5)and ρ(Ta2O5)in the range of 0-6 μg/mL.The correlation coefficients of calibration curve for niobium and tantalum were both 0.999 9.The detection limits for niobium and tantalum were 0.018 μg/mL and 0.051 μg/mL,respectively.The proposed method was applied to the determination of actual sample,giving the recovery rate of 97 %-102 % and the relative standard deviations(RSD,n=6) of 0.23 %-0.86 % for niobium and 1.5 %-2.3 % for tantalum.This method was applied to the analysis of standard sample,and the results were consistent with the certified values.