The content of five elements in wollastonite,including calcium,magnesium,aluminum,iron and manganese,was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) with Ca 317.933 nm,Mg 285.213 nm,Al 396.153 nm,Fe 238.204 nm and Mn 257.610 nm as analytical lines under the following experimental conditions:power of 1.2 kW,plasma cooling gas flow rate of 15 L/min,auxiliary gas flow rate of 0.2 L/min,atomizing gas flow rate of 0.8 L/min and sample uptake amount of 1.5 mL/min.The dissolution of sample was discussed.The results showed that some samples could not be directly dissolved in acid.Therefore,two sample treatment methods,direct acid dissolution and acid dissolution-alkali fusion,were proposed.When the sample was directly dissolved by hydrochloric acid,nitric acid and hydrofluoric acid,the matrix effect had no influence on the determination of Ca,Mg,Al,Fe and Mn.The matrix effect existed when the sample was treated by acid dissolution-alkali fusion.However,it could be eliminated by matrix matching method.In order to improve the precision and accuracy of the determination of high content Ca in wollastonite,the yttrium was used as internal standard.The proposed method was applied to the determination of standard and actual wollastonite samples,and the results were consistent with the certified values and those obtained by wet method.The relative standard deviations (RSD,n=8) were less than 2.5 ％.%在功率为1.2 kW,等离子体冷却气流量为15 L/min,辅助气流量为0.2 L/min,雾化器流量为0.8 L/min和样品提取量为1.5 mL/min的实验条件下,以Ca 317.933 nm、Mg285.213 nm、Al 396.153 nm、Fe 238.204 nm、Mn 257.610 nm作为分析线,电感耦合等离子体原子发射光谱法(ICP-AES)测定了硅灰石中Ca、Mg、Al、Fe和Mn 5种元素含量.对试样的溶解进行了探讨,结果表明有部分试样不能直接溶于酸中,因此提出了直接酸溶解和先酸溶后碱熔回渣的两种样品处理方法.直接用盐酸、硝酸和氢氟酸溶解试样,基体效应对Ca、Mg、Al、Fe和Mn测定几乎没有影响;而酸溶后碱熔回渣处理试样存在基体效应,但是可以采用基体匹配方法消除.为了改善测量硅灰石中高含量Ca的精密度和准确度,测定时采用钇为内标元素.方法已用于硅灰石标准样品和实际样品的测定,测定值与认定值或湿法的测定值相吻合,测定结果的相对标准偏差均小于2.5％(n=8).
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