2003 Volume 52 Issue 7 Pages 527-532
Minor constituents of TiO2, MnO and P2O5 in standard silicates were determined sequentially using a single acid decomposed sample solution by FIA. The FIA system simply consisted of 2 streams without heating, common to all constituents. The residual F in the sample solution changed from 20 to 140 mM, proportional to the sum of the coexisting Al, Fe, Mg and Ca. The TiO2-H2O2 complex was measured in 1 M HClO4 and 0.2 M H3BO3, eliminating Fe and F interferences, respectively. Mn(II) was oxidized rapidly by NaIO4 in the presence of MnO4− as an autocatalyzer in 0.2 M H3PO4. P2O5 was measured by the “Micell-molybdenum yellow method” using Triton X-100 to improve the sensitivity and to avoid F interference. The obtained analytical results were reproducible and agreed fairly well with those by batch and ICP-AES methods and with the certified values. The proposed sample decomposition was carried out for 10 samples/3 h in parallel.
