ICP-AES Determination of Cd, Sn and Zn in Uranium-Niobium Mixed Oxide

The uranium-niobium mixed oxide sample (0.200 0 g) was digested with HNO₃ (8 mL) and HF (2 mL) in microwave system. The CL-TBP extraction column was used to separate Cd, Sn and Zn from U. ICP-AES was applied to the determination of Cd, Sn and Zn in eluent. Analytical spectral lines of 226.502, 189.989 and 213.856 nm were chosen for the determination of Cd, Sn and Zn respectively. Linear relationships between values of emission intensity and mass concentration of the 3 elements were kept in definite ranges, with detection limits (3s) in the range of 0.003-0.02 mg·L^-1. Values of recovery found by standard addition method were in the range of 94.0%-101%, and values of RSD's (n=6) in the range of 3.7%-7.4%.