ICP-AES Determination of 13 Impurity-Elements in High-Purity Niobium Oxide

1.000 g of Nb2O5 was digested with 2 mL of HF at 120 ℃ and under a pressure larger than 138 kPa for 20 min in the MARS 5 Microwave Disgestor.The sample solution obtained was diluted to 100 mL in a volumetric flask,and used for AES determination.Matrix effect of niobium was eliminated by matrix matching method,i.e.a definite amount of niobium was added to each of the test solutions in preparation of calibration curve.Some other influential factors,including the choice of analytical spectral lines,background correction and etc.,were also studied and optimized.Test for recovery was made by adding different amounts of standard solutions of the 13 elements to niobium matrix,and values of recovery obtained were in the range of 90%-120%,and values of RSD′s (n=6) found were in the range of 1.0%-10.0%.Detection limits (3σ) of the method for the 13 elements were in the range of 1.3 to 42.0 μg·L-1.