Investigation of the Property Constants of Both Al and Cu Complexes with Picramine Ca and Using Competition Coordination for the Selective Determination of Trace Amounts of Cu

摘要

The reactions between Cu(II) and picramine CA (PCA) and Al(III) and PCA were both sensitive at pH 7. The competition coordination between Cu and the Al-PCA complex was applied to the selective determination of Cu (CCSD) by the spectral correction technique. Results have shown that the complexes formed at pH 7 are Al_2(PCA) and Cu(PCA)_3, their cumulative stability constants are 4.43 * 10~5 and 2.08 * 10~(15), respectively, and their real molar absorptivities are 5.78 * 10~3 at 650 nm and 3.19 * 10~4 at 530 nm. At the analysis of the samples, the relative standard deviation (RSD) was 5.0% and the recovery rate of Cu was between 94 and 108%.