电感耦合等离子体原子发射光谱法应用于铅锌冶炼烟尘中铟物相分析

Application of inductively coupled plasma atomic emission spectrometry in phase analysis of indium in lead-zinc smelting dust

铅锌冶炼烟尘中铟以硫化铟、氧化铟、硫酸铟等形式存在,样品经适当试剂分离后,利用电感耦合等离子体原子发射光谱法（ICP-AES）测定硫化铟、氧化铟、硫酸铟中的铟,与经典萃取-原子吸收光谱法、极谱法、比色法比较,ICP-AES快速、准确。对各相选择性溶剂及溶剂用量、样品溶解条件、元素分析谱线、仪器操作参数、基体效应、干扰的影响及消除等进行了探讨,并优化样品处理和测定条件。采用基体匹配和离峰扣背景方法,有效消除了测定的干扰。用加入高纯试剂配制的参考物质验证测定结果,铟物相中各相的铟量测定值与加入量相符。方法的线性范围为0.0~100mg/L,铟的检出限为0.072mg/L。对多个铅锌冶炼烟尘样品进行铟物相分析,氧化铟、硫化铟、硫酸铟及其他相中铟含量的加和与总铟量相当;总铟和氧化铟、硫化铟、硫酸铟中铟测定结果的相对标准偏差在0.96%~7.1%之间,标准加入回收率在88%~113%之间,实测样品与萃取AAS法测定结果无显著性差异。方法实用、快速,适于实际批量样品中铟的物相分析。

Indium in lead-zinc smelting dust existed in the form of indium sulfide, indium oxide and indium sulfate. The samples were separated with proper reagents. Then, the content of indium in indium sulfide, indium oxide and indium sulfate was determined by inductively coupled plasma atomic emission spectrometry （ICP-AES）. Compared to the classical extraction-atomic absorption spectrometry （AAS）, polarography and colorimetric method, the proposed method was rapider and more accurate. The selective solvent for each phase, the dosage of solvent, the dissolution condition of sample, the analytical line of elements, the parameters of instrumental operation, the matrix effect, the influence and elimination of interference were discussed. In addition, the treatment and determination conditions of samples were optimized. The interference was effectively eliminated by matrix matching and off-peak background deduction. The determination results were verified using the certified reference materials prepared by high-purity reagents. The found results of indium in each component were consistent with the added values. The linear range of method was 0.0-100 mg/L. The detection limit of indium was 0. 072 mg/L. The phase analysis of indium in several lead-zinc smelting dust samples was conducted. The content of indium in the form of indium oxide, indium sulfide, indium sulfate and other phases was equivalent to the total indium content. The relative standard deviations （RSDs） of total indium, indium oxide, indium sulfide and indium sulfate were between 0.96% and 7.1%. The recoveries were between 88% and 113%. The found results of actual sam- ples were consistent with those obtained by extraction-AAS method. The proposed method was practical, rapid and applicable for the phase analysis of indium in large amounts of samples.