恒温电热板湿法消解-ICP-AES对地质样品中铌和钽的连续测定

通过恒温电热板加热,用硝酸-氢氟酸-硫酸(体积比为6:5:1,V/V/V)混合酸消解试样,酒石酸定容后用电感耦合等离子体-原子发射光谱法对铌钽矿石中的铌钽连续测定,所加试剂引起的干扰通过空白实验予以消除。铌、钽谱线的发射强度与x(Nb2O5)和x(Ta2O5)在0—8μg/mL的范围内呈良好的线性关系。方法的检出限分别为0.021、0.048μg/mL,方法用于地质样品中铌、钽的分析,加标回收率为95.6%—108.3%,铌和钽的相对标准偏差(n=6)为0.21%—1.56%;用于标准样品分析,测定值与认定值相符。此方法很好的解决了地质调查样品的批量大并要求快速出结果的难题。

Continuous Determination of Niobium and Tantalum in Geological Samples by ICP-AES with Constant Temperature Electric Heating Plate Wet Digestion

The samples were digested with acid mixture of hydrogen nitrate-hydrofluoric acid-sulfuric acid compound(6∶5∶1,V/V/V) by the constant temperature electric heating plate,and the niobium and tantalum in niobium-tantalum ore digestion liquid were continuously determined by inductively coupled plasma atomic emission spectrometry(ICP-AES) after the digestion liquid was metered volume by tartaric acid,and the interferences of adding reagent were eliminated by blank experiment.There were good linear relation between the emission intensity of niobium and tantalum spectral line and concentrations of niobium and tantalum in the range of 0—8μg/mL.The detection limits of method were 0.021μg/mL for niobium and 0.048μg/mL for tantalum.The method was applied to analyzing the niobium and tantalum in geological samples,and the recoveries were from 95.6% to 108.3%,and RSDs of niobium and tantalum were in the range of 0.21%—1.56%,and the method was applied to analysis of standard samples,then the measurement value conformed to determination value.The method solves the problem for quickly obtaining the results of the multitudinous geological samples.