应用化学 ›› 1989, Vol. 0 ›› Issue (5): 39-43.

• 研究论文 • 上一篇    下一篇

碱性染料杂多酸多元配合物显色反应的研究 Ⅴ.乙基罗丹明B-磷钼杂多酸-聚乙烯醇体系

贺晓唯, 许生杰   

  1. 中国科学院长春应用化学研究所
  • 收稿日期:1988-11-04 修回日期:1989-02-21 出版日期:1989-10-10 发布日期:1989-10-10
  • 基金资助:
    国家自然科学基金

STUDY ON THE COLOUR REACTION OF THE MULTICOMPONENT COMPLEXES OF HETEROPOLYACIDS WITH BASIC DYES Ⅴ.ETHYL RHODAMINE B-HETEROPOLYMOLYBDOPHOSPHORIC ACID-PVA SYSTEM

He Xiaowei, Xu Shengjie   

  1. Changchun Institute of Applied Chemistry, Academia Sinica
  • Received:1988-11-04 Revised:1989-02-21 Published:1989-10-10 Online:1989-10-10

摘要: 本文研究了乙基罗丹明B-磷钼杂多酸-聚乙烯醇(PVA)显色体系,提出了高灵敏度的测磷分光光度法。缔合物最大吸收λmax=584nm。表观摩尔吸光系数ε586为3.2×105L·mol-1·cm-1。提高介质酸度和添加还原剂可消除SiO32-、AsO43-等的干扰。缔合物中P(V):ERB+=1:4。红外光谱研究证明,染料阳离子与杂多酸阴离子形成了离子对缔合物。本法可用于钢样及试剂中磷的测定,测定下限达1×10-5%(1g试样)。

关键词: 乙基罗丹明B, 磷钼杂多酸, 分光光度法

Abstract: A new sensitive colour system of Ethyl Rhodamin B-molybdophosphoric acid-PVA has been studied. The optimum conditions for pbosphorus determination are [HNO3]=0.56mol/dm3,[MoO42-]=2.4×10-2mol/dm3, [ERB+]=8.0×10-5mol/dm3 and 0.12% PVA. Theion-associate exhibits maximum absorptivity at 584nm. At the working wavelength of 586nm its apparent molar absorptivity was found to be 3.2×105 L·mol-1·cm-1.Beer′s law isobeyed in the range of 0 to 1.5μg of P(V) per 25mL. The colour of the aqueous solutionwas stable for at least lh. The molar ratio of P(V) to FRB+ in ion-associate was estab-lished to be 1:4. Infrared spectra studies show that an ionic bond occurs between ERBand phosphomolybdate and that the structure of the dye molccule is not of effected by the for-mation of the ion-assosiate.The effect of inteifering ions, such as As(Ⅴ), Si(Ⅳ) can bedecreased by increasing the acidity and adding mixed reductants. Phosphorus in steel andsome chemical reagents were determined directly at 1×10-5% level by the proposed methodwith satisfactory results.

Key words: Ethyl Rhodamine B, Heteropolymolybdophosphoric acid, Specetrophotometry