锗钨杂多酸 -丁基罗丹明B -聚乙烯醇离子缔合显色反应的研究

Study on a Colour Reaction of the Tungstogermanic Acid Butylrhodamine B-PVA

在强酸介质中,锗钨杂多酸-丁基罗丹明B(BRB)-聚乙烯醇产生高灵敏的缔合显色反应.该缔合物的λmax为580nm,表观摩尔吸光系数为2.16×106L·mol-1·cm-1,锗量在0～20μg·L-1范围服从比耳定律,缔合物可稳定48h以上,缔合物中Ge,W和BRB的摩尔比为1∶12∶4.考察了30多种共存离子的影响,大多数常见元素不干扰锗的测定,本法用于人参样品中锗的测定。

A colour reaction of ion association complex of the germanium(Ⅳ) tungstate butylrhodamine B was studied in the presence of 0.08% polyrinyl alcohol (PVA) in 0.96?mol·L -1 —1.16?mol·L -1 sulfuric acid medium.The maximum absorbance of the ion association complex is at 580?nm.The apparent molar absorptivity is 2.16×10 6?L·mol -1 ·cm -1 .Beer's law is obeyeed in the range of 0—20?μg·L -1 .The ion association complex was stable for at least 48?h.The malar ratio of Ge to W to BRB in the ion assocition complex was established to be 1∶12∶4.The influence of 30 diverse ions was examined.Most common ions do not interfere.The method can be applied to the spectrophotometric determination of micro germanium in some ginseng with satisfactory results.