Abstract：Barium carbonate is used as a kind of tracer in smelting of vanadium-titanium magnetite to calibrate the blast furnace slag carried in molten iron during tapping process. In order to accurately determine the content of barium, the inductively coupled plasma atomic emission spectrometry (ICP-AES) for the determination of barium in vanadium-titanium blast furnace slag was established based on several experiments. The sample was digested using mixed hydrofluoric acid, hydrochloric acid and nitric acid. The residual hydrofluoric acid was removed by evolution of perchloric acid fumes. After dissolving the salts using hydrochloric acid, the content of barium was directly determined by ICP-AES. The influence of matrix effect, spectral interference and background noise caused by vanadium-titanium blast furnace slag complex coexistence system was investigated in detail. The analysis line of barium with proper sensitivity (Ba 230.424 nm, 233.527 nm, 413.066 nm, 455.403 nm and 493.409 nm), detection integration, background correction area and the working parameters of ICP spectrometer were optimized and selected. The testing results showed that the main coexisting matrix elements (vanadium, titanium, iron, calcium, magnesium and aluminum) had no spectral peaks in scanning window of analysis line. In addition, they were consistent with the signal baseline of regent blank, indicating that the matrix components in vanadium-titanium blast furnace slag had no matrix effect and spectral interference in the determination of barium. Therefore, the correction measures of matrix matching were not adopted in this method. The calibration curve was directly plotted using the standard solution of barium. For the analysis lines of Ba 230.424 nm, 233.527 nm, 413.066 nm, 455.403 nm and 493.409 nm, the limit of quantitation for the method was in range of 0.000 2%-0.001 0%, the background equivalent concentration was in range of 0.000 3%-0.000 5%, the relative standard deviation (RSD) was less than 2.5%, and the recoveries of standard addition were between 93% and 102%. The proposed method was applicable for the determination of barium with mass fraction of 0.005%-2.50%.
