| Chromium contents in CoCrPtSiO2, AuNiCr, NiPdCrBSi, NiCrB alloy were determined by using atomic absorption spectrometry, the interference from other elements in the determination was investigated and the eliminating method was given. After the sample is transferred into the aqueous solution with a mixture of hydrochloric acid, nitric acid and hydrofluoric acid, the remaining hydrofluoric acid in the sample is dispelled by using perchloric acid. And then Ni(II) and Si(IV) are removed by precipitation with ammonium chloride, whereas Au(III) is removed by reduction with hydrazine hydrate. The conversion of Cr(VI) into Cr (III) gives rise to a final solution which will be submitted for AAS measurements. The standard working curve is linear in the range of 0~6.00 μg/mL with a detecting limit of 0.004 μg/mL. When chromium content is between 5% to 7% in the samples, the relative standard deviation can be less than 1.29%. The recovery for standard addition ranges from 93.34% to110.80%. |
