【摘要】 改进了游离二氧化硅 (fSiO2 )测定中试样的分解方法 ,采用硫 -磷混酸替代单独使用磷酸分解试样 ,防止了焦磷酸盐的形成 ,同时 ,氟硼酸对fSiO2 的溶解率符合测定要求。改进的方法用于标准物质中fSiO2 的测定 ,结果与标准值或磷酸溶矿重量法相符。对于w(fSiO2 ) =3 .2 6 %的标样 1 0次测定的RSD为 2 .4%。更多还原

【Abstract】 The sample decomposition method in analysis of free SiO 2 in rocks, minerals and dusts was improved. Sulphuric phosphoric mixed acid was used instead of phosphoric acid alone to avoid the formation of pyrophosphates. And the solubility of free SiO 2 in HBF 4 can also meet the needs for the determination of free SiO 2. The improved method has been used in the determination of free SiO 2 in standard samples. The results are in agreement with certified values and those obtained by weight method with sample preparation using phosphoric acid. The precision for analysis of the standard sample with w (fSiO 2) =3.26% is 2.4% RSD ( n =10).更多还原