电感耦合等离子体原子发射光谱法测定铁矿石中16种元素

准确、快速地测定铁矿中各种杂质元素含量,对铁矿石质量判定具有重要意义。试验采用“酸溶-碱熔回渣”的方法消解样品,先用硝酸、盐酸溶解样品,再过滤,滤渣及滤纸灰化后再用碳酸钠-硼酸混合熔剂熔融,溶液中的总固体溶解量(TDS)为2.5mg/mL。采用基体匹配法绘制校准曲线消除基体效应的影响,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定铝、砷、钙、铬、铜、钾、镁、锰、镍、磷、铅、硅、锡、钛、钒、锌等16种元素。各待测元素校准曲线的线性相关系数均大于0.999;方法检出限为0.00018%~0.034%。实验方法用于2个铁矿石实际样品中铝、砷、钙、铬、铜、钾、镁、锰、镍、磷、铅、硅、锡、钛、钒、锌的测定,结果的相对标准偏差(RSD,n=8)为0.40%~9.8%;按照实验方法测定4个铁矿石标准样品,测定值与认定值相吻合;测定4个铁矿石生产样品中铝、砷、钙、铬、铜、钾、镁、锰、镍、磷、铅、硅、锡、钛、钒、锌,测定值与GB/T 6730系列标准方法测定值相吻合。

Determination of sixteen elements in iron ore by inductively coupled plasma atomic emission spectrometry

The accurate and rapid determination of impurities in iron ore has important significance to judge the quality of iron ores. The sample was digested using the method of “acid dissolution-alkali fusion of slag”. The sample was dissolved with hydrochloric acid and nitric acid followed by filtration. The filter residue and filter paper were ashed and then melted with sodium carbonate-boric acid mixed flux. The amount of total dissolved solids (TDS) in solution was 2.5mg/mL. The calibration curve was prepared with matrix matching method to eliminate the influence of matrix effect. The contents of 16 elements (aluminum, arsenic, calcium, chromium, copper, potassium, magnesium, manganese, nickel, phosphorus, lead, silicon, tin, titanium, vanadium and zinc) were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The linear correlation coefficients of calibration curves for testing elements were all higher than 0.999. The detection limits of method were between 0.00018% and 0.034%. The proposed method was applied to the determination of aluminum, arsenic, calcium, chromium, copper, potassium, magnesium, manganese, nickel, phosphorus, lead, silicon, tin, titanium, vanadium and zinc in two actual samples of iron ore. The relative standard deviations (RSD, n=8) of the results were between 0.40% and 9.8%. Four standard samples of iron ore were determined according to the experimental method, and the found results were consistent with the certified values. The contents of aluminum, arsenic, calcium, chromium, copper, potassium, magnesium, manganese, nickel, phosphorus, lead, silicon, tin, titanium, vanadium and zinc in four production samples of iron ore were determined, and the found results were consistent with those obtained by standard methods in GB/T6730 series.