Mo（Ⅵ）与Tiron的显色反应及应用研究  

COLOUR REACTION OF MO(Ⅵ ) WITHTIRON AND ITS APPLICATION

作　　者：陈玉銮[1] 王占文[1] 周向阳[1] 

机构地区：[1]南京化工学院应用化学系,北京化工二厂

出　　处：《南京化工学院学报》1994年第1期22-26,共5页

基　　金：江苏省科委基金

摘　　要：研究了Ｍｏ（Ⅵ）与Ｔｉｒｏｎ的反应，发现在ｐＨ４．０的ＨＡｃ－ＮａＡｃ介质中形成１：１配合物，该配合物在２５２ｎｍ、３１５ｎｍ有两个吸收峰，而在可见光区无吸收峰。测得ε２５２＝６．９×１０￣３Ｌ·ｍｏｌ－１·Ｃｍ－１，ε３１５＝３．５×１０３Ｌ·ｍｏｌ－１·Ｃｍ－１。据此建立了测定Ｍｏ（Ⅵ）的方法，在２５２ｎｍ和３１５ｎｍ处的线性范围分别为１．６×１０－６ｍｏｌ·Ｌ－１～２．Ｏ×１０－４ｍｏｌ·Ｌ－１和３．２×１０－４ｍｏｌ·Ｌ－１～２．０×１０－４ｍｏｌ·Ｌ－１。检出限分别为８．Ｏ×１０－７ｍｏｌ·Ｌ－１和１．６×１０－６ｍｏｌ·Ｌ－１．ＰＯ＿４￣３＋、ＳｉＯ＿３￣２－对测定无干扰，而Ｗ（Ⅵ）、Ｖ（Ⅴ）、Ｆｅ（Ⅲ）等有干扰。该法试用于有机磷合钼聚多酸盐样品的测定，结果满意，方法回收率９６％～１０２％，变异系数≤１．ｌ％（ｎ＝１２）。A method is presented for the UV-spectrophotometric determination of Mo (Ⅵ ), which isbased on its reaction with Tiron in HAc-NaAc (pH= 4. 0)medium. Mo (Ⅵ ) forms a complex withTiron with two maximum absorptions at 252nm and 315nm,and their apparent molar absorptivitiesbeing 6. 9 × 103L. mol-l. cm-l and 3. 5 × 103L. mol-l. cm-1, respectively. The composition ofthe complex is found to be l: 1. Its formation constant is logK' ML= 5. 15 ± 0. 01. The determination range of l. 6 × 10-6mol. L-1￣ 2. 0 × 10-4mol. L-1,the detection limit of 8. 0 × 10-7mol.L- l, the recovery rate of 96 % - 102 %,and the variation coefficient of 1. 1 % (n= 12 ) are given. Ithas been applied to the determinatin of Mo in organo-phosphorus polymolybdates with satisfactory results.

关 键 词：钛铁试剂 钼 紫外分光光度法 显色反应 

分 类 号：O614.612[理学—无机化学] O657.32[理学—化学]