改进的极谱法测定化探样品中的钨钼

Determination of Tungsten and Molybdenum in Geochemical Exploration Samples by Modified Polarography

摘要: 试样经氢氧化钾熔融，水提取，采用二苯乙醇酸代替苯羟乙酸，在硫酸-二苯乙醇酸-二苯胍-氯酸钾体系中，利用JP—06A精密极谱分析计测定钨、钼，使测定的灵敏度大为提高。钨、钼的峰电位分别为-0.76 V、-0.26 V（相对饱和甘汞电极），钨、钼含量在1.0～100.0 ng/mL时，峰高与浓度呈线性关系。方法经国家一级标准物质检验，测定结果与标准值吻合，方法精密度（RSD，n=12）钨、钼均小于5%。

Abstract: The sample is melted with potassium hydroxide and extracted with deionized water. In sulfuric aciddiphenyl glycollic aciddiphenyl guanidinepotassium chlorate system, tungsten (W) and molybdenum (Mo) produce polarographic catalytic waves with peak potentials (vsSCE) at -0.76 V and -0.26 V, respectively. The method provides the high sensitivity and wide dynamic linear range (1.0～100.0 ng/mL for W and Mo). The method has been applied to the determination of W and Mo in National Standard Reference Materials and the results are in agreement with certified values with precision of less than 5%RSD