混合增溶剂多元配合物体系光度法测定铌  

Spectrophotometric Determination of Niobium as Ion-associated Complex in the Presence of Mixed Solubilizing Agents

作　　者：陶慧林[1] 

机构地区：[1]桂林工学院应用化学系

出　　处：《岩矿测试》1995年第4期298-300,共3页Rock and Mineral Analysis

摘　　要：研究了在聚乙烯醇和阿拉伯胶混合增溶剂存在下，铌钼酸根与结晶紫形成的缔合物直接在水相中光度法测定Ｎｂ。该方法线性范围０～０．４μｇ／ｍｌＮｂ，ε＿６４４为３．７×ｌ０；大多数共存离子不干扰测定，在增溶体系下提高了Ｔａ的允许量；有色体系稳定时间为２ｈ，是目前测定Ｎｂ的灵敏度高、选择性较好、线性范围较宽的水相光度法之一。对于含Ｎ６量在１０￣－４～１０￣－３级的试样测定６次，其ＲＳＤ在１．９％～３．２％；经标样分析验证，其结果与标准值相符。he basis of the determination is the formation of an ion-associated complex of molybdoniobate heteropoly acid and crystal violet in the presence of polyvinyl alcohol and arabic gum.Beer's law is obeyed in the range O to 0.4 μg/ml Nb,the molar absorptivity of the complex is 3.7×10￣5L·mol￣-1·cm￣-at 644 nm.Most foreign ions do not have effect on the determination,and the color is stable for 2 h.The method shows prornise for the determination of Nb by aqueous spectrophotometry with respect to sensitivity,selectivity,and the available range of linearity.The method gave fairly good results in the analysis of reference samples and the RSDs obtained varied from l.9%to3.2%(n=6)。

关 键 词：铌 分光光度法 配合物体系 混合增溶 

分 类 号：O614.512[理学—无机化学]