Direct determination of oxygen in oxidesulfides and double oxides of antimony by X-ray microanalyzer

Abstract

In X-ray microanalysis, direct determination of oxygen content is inevitable for the oxide-sulfide samples which contain both O^2- and S^2- not in the form of So₄^2- group but at the equivalent or the similar sites. X-Ray intensity was measured as the peak area of the oxygen K_α. For antimony, sulfur, calcium, manganese and iron the peak height was directly measured as their X-ray intensities. The ZAF correction was made for all the data obtained. The standard materials were Sb₂O₃ (synthetic) for oxygen and antimony, Sb₂S₃ (stibnite) for sulfur and antimony, CaSiO₃ (wollastonite) for calcium, Mn (metal) for manganese, and Fe (metal) for iron. Experimental results and the ideal formulas in the parenthese are as follows;kermesite : Sb_1.94S_1.95O (Sb₂S₂O), sarabauite:Ca_0.94Sb_9.85O₁₀S_5.71(CaSb₁₀O₁₀S₆), synthetic sarabauite Ca_0.97Sb_10.27O₁₀S_6.15, synthetic schafarzikite : Fe_0.87Sb_1.90O₄(FeSb₂O₄), synthetic manganese antimony oxide : Mn_1.06Sb_2.10O₄(MnSb₂O₄). The relative error of oxygen content between the experimental and the theoretical results ranges from-4.42% to 7.84%. The coefficient of variation of the intensity of oxygen K_α in Sb₂O₃, used as a standard, was less than 1.09 %.