The chemical components in alumina-chrome(AC)refractories were determined by X-ray fluorescence spectrometry(XRF)using glass beads(GB).AC refractories which contain much Cr
2O
3 can not be fused with only Li
2B
4O
7.Thus, LiNO
3 must be added as an oxidizing agent.The fusing conditions for the GB were chosen as follows:sample(0.2000g)-Li
2B
4O
7(3.0000g)-LiNO
3(3.000g), 1250°C-10min.Complete fusion of the Cr-containing sample was suspected to have been proceeded by the formation of CrO
42-, caused by the oxidation of Cr(III), converting it to Cr(VI).This possibility was investigated by the CrK-edge X-ray absorption near-edge structure(XANES)spectra.According to preliminary results of Cr(VI)by XANES, the Cr(VI)content in a GB prepared with only Li
2B
4O
7 was merely 7% against the total Cr, but in the GB with Li
2B
4O
7 and LiNO
3 it was 39%.Moreover, the Cr(VI)content in the GB with Na
2B
4O
7 and NaNO
3, which could be easily fused, but could not be used for actual analysis, because of the contain Na
2O content, was 95%.The GBs used for the calibration curve were prepared by accuratly weighing alumina system reference materials and reagent Cr
2O
3 on a micro-balance of 1μg accuracy limit and fusing them with Li
2B
4O
7 and LiNO
3.As a result, the accuracies(SD)of the calibration curves prepared with these GBs were very satisfactory for Al
2O
3:0.21mass%, Cr
2O
3:0.07mass%, SiO
2:0.027mass% and so on.
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